I remember WAYYY back when, in the late 1990's, when I was with the Western New York militia. There was a guy who ran things who, in retrospect, was obviously FBI. There was also a woman who orbited him, who also in retrospect was obviously a female agent.
One of the guys in the group began altering firearms to include illegal 'fun switches'. Well wouldn't ya know! He got raided and caught some Federal charges! What a coinky-dink!
You’ve noted key red flags for such groups. Add to it newbies pushing for more aggressive actions as well as illegal moves.