But I can't see any place on lemm.ee that lets me subscribe to it from my lemm.ee account. I searched for it under Communities, but it doesn't show up as an option.
I don't believe Squabbles is federated/using ActivityPub, so you can't connect to it through Lemmy. We can connect to Lemmy instances, as well as some other ActivityPub communities (most notably Kbin and Mastadon instances), but Squabbles is not using ActivityPub, it's an entirely separate social media.
Oh. Someone recommended sub.rehab as a place to search for communities. I didn't realize that site has non-Lemmy communities. I guess I'll stick with lemmyverse.
Click the hamburger icon in the upper left (talking as if you are in mobile web)
Go to communities.
The page always lists your local communities first, click all.