Google maps tracking device

Greetings,
I’m trying to use google maps to track a cell phone and have followed the the instructions to the letter (or so I think, but I’m missing something). I have tried on both my working HA and a VM that I set up for experimentation.

I have set up 2 accounts with google maps and share so that acct2 sees acct1. So good there.
I have captured the cookies in Chrome and renamed it. But I’m unclear if that includes the extension or not (.txt)
I edited the config.yaml file as per the docs, with the acc2 email address.

Problem: When I restart HA, or even reboot, no new devices appear. I don’t get a new known_devices.yaml file as per the docs, or a new devices anywhere. I even created a known_devices.yaml file, but nothing was added to is.

Are there prerequisites before this procedure? Please help as I know I’m missing something.
Thanks

I know it’s been a while, but if you’re still interested in using the Google Maps integration, I created a custom version that addresses several of its shortcomings, including making it easier to obtain a valid cookies file and get onto your system. It also lets you know when it’s going to expire soon, or if it has already expired, in which case it prompts you to grab & install a new set of cookies. More details can be found in the following topic:

Enhanced Google Maps Integration - Share your Projects! / Custom Integrations - Home Assistant Community (home-assistant.io)