WTBH, I don't know about ROs and other stuff like that but here is a little something to help you calm down. First take a couple of deep breaths, second remind yourself that you are not responsible for his seating and then let it go. Go to the recital, sit with you mom and enjoy yourself. Lastly whatever he does don't show anger and do your best to ignore it. You don't have to talk, look, respond or react with him in any way just because he wants to. If he starts to act like a jerk have your mom record it on her cell phone. Above all be civil and don't stoop to his level.
Remember, this event is for your daughter so do your best to make it good for her.
((((hugs))))
Your friend,