yah i can see it being an issue, you'd have to detect the SI attacking the player and prob set the collision group back to default. Don't know though...Imo more work than its worth. There is m_MoveCollide...not sure what its for but may be of some use. could've sworn there was an entprop or cvar you could set that makes players not push other players, so u could walk through them, if i find it i'll let you know.
sb_pushcale 0
But this command only works on survivors bots, I need this command, but for survivor players.