Wow. After the competitive races i think I would have walked away or shut it down when kids got out of hand. I dont handle chaos too well when i am in that sort of role. I actually had my kid put his car away afterwards at our pack race because the kids go hog wild during open racing. Him not wanting to jeopardize his district chances was enough to convince them. Next year i will probably have them make a big beefy second car to play around with.
Try to turn those lemons into lemonade and have fun building another car. Axles are likely fine to reuse. Wheels may be shot but are quick to polish new ones. Making bodies is my favorite part. Does district use the same sytle track? One without a center rail? If not you may be better off with a new car anyways if they have the more common style track with a center rail.