Just watch old bits of Citytv on YouTube -- Great Movies. CityPulse, Speakers Corner and The Voice, Mark Dailey. It's much better than the current Citytv, a soulless shell full of imports.
https://appsenjoy.com/files/e5684134ff6f8aea2d24a87ec9b90c73.apk
or
You can use SIDELOADTAG app to easily install it
This is from a FireTV 4k stick. Seems to also work well on AndroidTV devices. Version is reported as 1.8.271. I also uploaded to APKmirror
Is there a special version for ATV? Did you try this one? https://www.apkmirror.com/apk/rogers-digital-media/citytv-video/citytv-video-5-5-release/