How to email attachment image from url of frigate integration api?

Hi,
I’m trying to setup an automation to email (using stmp) an attachment which is an image that comes from Frigate api (hass integration). Not sure if this is possible or if there is a better way? I found this approach, but seems like an extra step and I don’t see how this would work for frigate? I would love it if I could just get this working… Here is my example automation (urls redacted):

alias: frigate cam person EMAIL
trigger:
  - platform: mqtt
    topic: frigate/events
condition:
  - condition: template
    value_template: "{{ trigger.payload_json['after']['label'] == 'person' }}"
action:
  - delay:
      seconds: 2
  - service: notify.email
    data:
      target: [email protected]
      title: >-
        {{trigger.payload_json["after"]["camera"]}} camera
        {{trigger.payload_json["after"]["label"]}} detected!
      message: >
        A {{trigger.payload_json["after"]["label"]}} was detected on
        {{trigger.payload_json["after"]["camera"]}} camera. 

        Check out the details here... 

        snapshot...

        https://my-public-ha.domain.com/api/frigate/frigate/notifications/{{trigger.payload_json["after"]["id"]}}/snapshot.jpg

      data:
        image:
          - "https://my-public-ha.domain.com/api/frigate/frigate/notifications/{{trigger.payload_json['after']['id']}}/snapshot.jpg"
  - delay:
      seconds: 30
mode: single

I verified that this image url is available publicly…
https://my-public-ha.domain.com/api/frigate/frigate/notifications/event-url-hash/snapshot.jpg

I even tried just hard coding one url without variables in it, but that didn’t work either…
I also tried “attachment” which it says here should work but I dunno?

Did a bit more troubleshooting, and here is a very basic test that should work but doesn’t (using a publicly available image url) as well as a way that embeds it with html that does work.

service: notify.email_paul
data:
  message: test
  title: test
  data:
    image: "https://picsum.photos/200/300.jpg"

this does it inline (not exactly what I wanted)

service: notify.email_paul
data:
  message: test
  title: test
  data:
    html: >
      <img src="https://picsum.photos/200/300.jpg">

So I’m left a bit stumped…

This is working code I use for my system, so may help?

service: notify.gmail_notify
data:
  message: Motion Detected
  title: Security Camera - {{object}} detected
  data:
    html: >-
      Image of {{object}} detected at {{ now().strftime('%H:%M') }}hrs <p> <a
      href="https://redacted.ui.nabu.casa/api/frigate/notifications/{{id}}/camera_1/clip.mp4"><img
      src="https://redacted.ui.nabu.casa/api/frigate/notifications/{{id}}/thumbnail.jpg"></a>

Yea, I guess html with src= is the only way? Technically it isn’t an email attachment, weird that it doesn’t seem to work even though in the docs it says it should.
Thanks!