This is just my experience/observations with said individuals they might turn a new leaf in the future. As I add more people I'll try to give as much context as possible.
Eznp he joined a few hell baalrun games and went hostile, one of them the host decided to fight him and the host lost.
CuteLilPanda Had joined a few games and went hostile. From talking to other players people have seen him kill in cow games.
Wenbo420#1303 Joins with a char named Wenbo, he's been around since the game launched. I haven't seen him kill anyone but he loves to join games and hostile.