The first photo shows two wires coming from the sensor; to the motor. One is power; one is the signal wire.
The second photo shows the rear of my motor; with the white signal wire going directly into the motor. This is what provides the signal to open / close; instead of using RF.
NO PAIRING REQUIRED! 
Unfortunately this does not work with garage door openers that have the Yellow Learn Button and the Yellow Antenna. For these, you will need to either wire in a working garage door opener remote or buy the Security+ 2.0 addon.
This was the other method of wired installation; forgot to mention that.
Although in my setup this was not required for me on a Genie brand motor - YMMV.
Great information, @ssilence!
Exactly right. It seems the “Security 2.0” systems (Chamberlain/Liftmaster, and a few others) send a pulsed signal along the wired connection. (I’ve never been entirely sure why this increases security as, in order to short the two wires that lead from the panel, you need to be in the garage already and, if you’re there, you can just push the button on the panel. 
)
At any rate, the add-on is something that generates that pulsed signal.
Alternatively (as I did in one of my previous attempts), you can wire the leads to the button on the panel or to the button on a remote which has been paired to your system. Either way works, but it involves soldering and voiding the warranty on either the remote or panel so some folks are shy to do it.
I’ve got the hardware on order right now. Specifically, the issue (as some have already noted) is that “Security + 2.0” openers from Chamberlain/LiftMaster send a coded pulse along the wires connecting the panel to the drive unit. (This seems like gilding the lily to me, but so it is.) This add-on either (I’ll let you know when I get it.) sends that coded pulse or acts like a remote control (and gets paired with the drive unit). The myQ add-on for those who don’t have a myQ drive with WiFi does the later. I did the former with a previous install, but would like to find a solution that doesn’t involve soldering. (Some folks lack the tools or the inclination.)
To work around “Security+ 20” I purchased an inexpensive (~ $10 USD) LiftMaster 883LM Security+ 2.0 MyQ Door Control Push Button. You solder a relay to the small push button so the relay simulates pushing the security+ button (not closing the circuit to the opener). You then wire up the button normally to the motor.
I use esphome (ESP12s Huzzah) to toggle the relay. I housed the ESP12s, relay, and button together in a project box on the motor near the convenient A/C outlet on the ceiling:
This is basically the same thing pashdown wrote about (see main thread and his photos in that link) and it’s been working for a couple years now.
For sensing the state of the garage door I use a simple Z-Wave magnetic door sensor (photo of installation in link):
Yes. Exactly what I was describing in my post preceding yours (but with less detail).
It works, but it’s clearly a kludge.
Some good options here. I had already ordered the MyQ home bridge 819LMB works with homekit before I saw this threads other good options.
Good news is that the homekit controller HA integration works great with it and gives you fully local control. I wrote up details and how to set it up in another thread. Fully local MyQ garage door control
You can block the 819LMB from the internet at the firewall and the myq app stops working and the data stays local. Works great. I actually don’t mind the beeping warning for closing. I think its at least a good idea with my kids around and now I don’t have any other hardware other than that myq hub. It is probably more expensive that these other options, but its clean and local.
For those of you wondering what the solution that Meross uses to allow its controller to work with Chamberlain/LiftMaster Security 2.0+ drives, it’s exactly what I kludged together when I was having this issue on another home automation platform and a different remote door opener (SmartThings and GoControl):
The solution is a remote with wires connected to one of the control buttons. You pair this remote with your door and then the Meross controller “pushes the button” for you.
I can tell you from prior experience that this works. The one downside is that the remote is battery powered so you have to periodically replace the 2032 battery.
Meross will send you this remote with the wires already connected (if you’re shy on soldering) at no additional costs. If you’d like to do the same thing and just want to do it yourself, you can purchase a low-cost remote that will work with your door and solder two wires to the leads of the primary button. Connect those leads to the leads coming from the Meross controller (polarity doesn’t matter. It’s a simple closed contact).
Thanks for this info. After the latest round of MyQ agita, i’ve ordered an OpenGarage with the Security 2.0 add-on to be done with it.
Please report back with your experience.
If I had to do it over again, that’s probably the direction I’d go (OpenGarage). As it is, Meross is working very well for me and (probably just to spite me) myQ has also started being reliable again 
I have been using MyQ for a few years, this summer we had a security system installed, and there was a 40 day wait till they could come. I decided I wanted to do most of the wiring myself, a full custom job, to support future home automation needs. All the garage wiring is protected inside EMT, then branches off if needed via aluminum flex.
What we ended up with is the security system monitors the door status, and also controls a relay which I had connected to the door opener where the wall button wires connect. The relay is controlled by either a zone event (or keyfob button), or by entering a command sequence on the keypad.
Integrating the alarm system into HA now allows me to control the door there as well using a script which send a keypad command string to the panel, tripping the relay for a few seconds.
So for controlling the garage door I now have:
MyQ (for now…)
Door remotes and wall buttons
Alarm system keyfob
Alarm system keypad
Home Assistant scripts and automations
I have not used MyQ or the door remotes in months, HA is so much more convenient since that is where I would arm/disarm the alarm from anyway. The alarm keyfobs are also 2-way handshake encrypted which makes them far more secure than a rolling code door remote.
It is also far faster than MyQ for closing the door, since that thing beeps for like 10s, and faster to open since no cloud. Plus it is more reliable (beyond no 3rd party service reliance), the MyQ door sensors will say the door is open when it is windy out, even though they are closed, and there is no longer a replaceable battery in the sensor loop since it is all hardwired. Also, the MyQ is not in a location where it can be plugged into a UPS, so if the power is out it will no longer report door status or open the door (motor has a battery which can open/close door once).
Got the Opengarage installed today. So far so good. Physically the install is easy - the “Security 2.0 addon” is just a modified Chamberlain opener button, and the whole thing took no more than 10 minutes to mount.
The firmware setup was a little finicky at first - AP mode worked fine, but it didn’t like my wifi for some reason. Finally fixed it. It’s been stable for about 6 hours. Right now it’s using the HA integration that uses http polling, but I’ve also got MQTT partially working - the MQTT setup shows state but i can’t figure out how to control the door yet. But very pleased not to be worrying about another Myq API problem.
I’m fairly positive on the whole [modified remote with wires soldered to the main button] “Security 2.0 add-on” solution. The only caveat in my thinking is that you need to periodically check the battery on the remote. (It needs a second add-on to report battery status )
Let us know if you get MQTT working. I’d be interested in that.
Got MQTT working for control as well as state. The API is not well documented, but the two keys for me were:
Using this updated, forked firmware for the OpenGarage device - GitHub - gabe565/OpenGarage-Firmware: OpenGarage: open-source WiFi-enabled garage door opener
Figuring out that for whatever reason, OG was not accepting the “open” or “close” payload on the command topic “GarageDoor/IN/STATE”, but would accept “click”
I will keep both the polling and the MQTT solution going in parallel while I test for robustness.
configuration.yaml:
cover:
- platform: mqtt
name: "Garage Door"
command_topic: "youropengaragedevicename/IN/STATE"
state_topic: "youropengaragedevicename/OUT/STATE"
state_open: "OPEN"
state_closed: "CLOSED"
payload_open: "click"
payload_close: "click"
device_class: "garage"
sensor:
- platform: template
sensors:
garage_door_status:
friendly_name: 'Garage Door Status'
value_template: '{{states.cover.garage_door.state}}'
groups.yaml:
garage:
name: Garage
entities:
- cover.garage_door
- sensor.garage_door_status
This is all stolen from a thread here:
There is a fancier version that has all the distance info and car parked info that i’m going to try to implement next.
I haven’t read the thread but i use OpenGarage. It was cheap, easy to put into Home Assistant and works everytime. I had to buy the Security+ 2.0 addon but it’s great, had it installed in about 15 minutes.
i would like to get MQTT working as well, hoping to avoid the polling by HA. is this all you needed to do to get it working? i have MQTT installed but have nothing working with it.
You’ll have to do a bit of config on the opengarage device to point it at the MQTT server, but yeah, that’s about it.
i can’t get this working. do you need to setup the mqtt tab on the stock opengarage interface?