So I did figure out that yes, #Mastodon can federate #Lemmy and #Kbin content. The problem is that Mastodon doesn't know what to do with it, so it (the group) looks like a user that boosts all posts and comments.
I found myself browsing the "federated group" @selfhosted over on https://kbin.social, as I think Kbin has a nicer UX for it.
I didn't really want to create a separate account for group stuff, but that might be what we do in the short term. 🤔
