A static is an entirely unofficial group of people to the game, it's just a few people personally agreeing to play together. The rules of the game have no bearing who can and can not be in that group. You are not required to remove anyone from your static even if they got banned ingame. You are free to remove anyone from your static for any reason (or even no reason at all). You are not free from the consequences of doing so because no one is required to stay in your static if they do not want to stay.
The fact that this needs to be explained to a static leader should be weird but OP's lack of understanding has already exploded the group so at this point all that is left is to learn from it.