Maybe go ahead and post it on the AMA community and then make a crosspost on the !newcommunities saying you are reviving the AMA community with your AMA. I would message the mods here and see if they’d let you crosspost it here as well. If we want AMAs to be a thing on the fediverse we need communities that are OK with helping host them until the AMA community gets its legs under it
Edit: I noticed you mentioned the AMA community is hosted on hexbear. maybe try starting a new community on an instance that isn’t widely maligned and defederated such as Lemmy.world or Lemmy.ml