No worries, I’ve never had the joy of running a Lemmy instance, and that certainly leaves me lacking some perspective/info, but as a user I’ve run across and reported more than my fair share of peculiarities (especially with federation).

At this point, trying to act as an intermediary between 2+ different instance admins to figure out where things are going wrong is a practiced (if not well-oiled) process.

Unfortunately, with two instances involved, it’s always hard to tell where things go wrong, but so far I’ve observed that:

• neither instance has the other blocked
• both appear in each others Linked Instances
• the initial requests to visit the comms did cause some activity to federate (this part has me particularly stumped!)
• there doesn’t appear to be anything in the instance/comm sidebars that matches the lemmygrad slur filter (yes, that would break federation)
• I was successfully able to subscribe from two other instances, which suggests that getting the grad admins to see my post to them & take a peek too is probably necessary to get to the bottom of this one