After resetting the federation status, a lemmygrad admin said:
The server must have had an originally misconfigured nodeinfo, or we had a network blip. It’ll need to wait a day to re-fetch the nodeinfo (done daily) so that it can start sending to it.
We need to wait for lemmygrad re-fetch the site info for r1b.it, which should happen in ~ 22 hours from now. I have a reminder set to check again then.
That was about 1.5 hrs ago, so hopefully I’ll be able to subscribe there soon! Thanks again for helping look into this!