No worries. Those are the more community-friendly of the bumble bee cats. Those guys are fine for this set-up IMO
Red minors can be a bit nippy IME. If you get them, just keep an eye on tankmates for signs of nips. If you wanted to consider a different tetra, bentosi tetras, bleeding heart tetras, and diamond tetras have the same shape but with less nippiness. Personally, I would not put red minors in with gbr in one of my own tanks, but some people have better experiences with the red minors than I did.
Skirt tetras can be nippy, but mine never had an issue with my rams, so I think they would be a better choice. I am a fan of the white skirt tetras. The long fins of the rainbows might make an appealing target, but I think it is worth trying and would likely be ok.
I would start with just the catfish, gbr and 2 schools (1 tetra school and 1 rainbow school). That will probably be pretty good for this tank. Skirt tetras can get decently large. I would also add another couple of banjo cats if possible. They will cruise around together in groups at night, and it is fun to watch. They are not a high bioload catfish anyways, so a few more wouldn't stress your bioload capacity.