I agree. Start with a fresh door and consider this a lesson learned.I would throw them all out. New they cost $19 each here in NJ and possibly less in other states. You will spend 2 hours to fix each one and that's more than $19 I would think. You will have some labor costs to re install hinges but that's still less than sanding, prime and re-paint. Also if you sand too much the graining will be a mess so it all should be done by hand.
Dont waste your time on the plastic covered door.
I have dropped doors moving them and the best fix was a new door.
Time is money, and wasted time is wasted money.