"If the player was hurt (slamed to ground) during play in a tight crowd in front of a goal I can see how that could be missed. (depending on how it happened) "

Agreed, if it were an isolated incident. If it were an alleged pattern of behaviour, I think I would be watching.

I don't agree that the referee is exempt from controlling off field behavior. I have seen referees stop games and threaten parents with expulsion for persistent abusive language. And it was the right thing to do.

Not saying the home school doesn't have primary responsibility. But again.....the referee has to protect the players and keep control of the game. And if the off-field stuff threatens to spill out onto the field....thats where the ref has to take control.

IMO.