Anvil's exactly right. You file what you're entitled to, and he's responsible for his own filing. If he claims when he's not entitled to claim, oh WELL. Guess he gets a tax penalty (and, god willing, a full audit).
He's trying to make you responsible for what he does. You don't have to have any exchange whatsoever about it. He knows he isn't current, so he's not entitled to the allowance. Period.