Hope you have all transactions/receipts. If you do, I would give Sony 1 more call and tell them "if I don't get my answers TODAY, I'm filing a claim in small claim court".
If they don't give you answers, do just that.
Take them to court for the amount AND court fees (should cost you about $50-100 bucks).
I guarantee they will cut you a check SOMEWHERE along the line as it is not worth it for sony to send a lawyer to your area for a BS case.