Just look at the seller's recent purchase history and then enjoy your HGE mini ST gaudens 'bullion' coins. Edit: didn't see second page that you've been offered a refund which is good luck on your part. But in the future just check the sellers feedback as a buyer and if you had you'd of seen that they had purchased many of these mini 'gold' bullion coins and avoid yourself a hassle.
Yeah this could backfire on you. The seller can argue that they fulfilled the intent of the auction by sending you one of those mini ones worth $25. They come up with new schemes every day it seems. I was just at a show and 1/10th oz AGEs were going for $190 to $200. Don't expect much gold for $96 even if the auction was legit.
I went into this with my eyes wide open. There's always a chance that someone is selling coins without a clue to their value (happens all the time, even though people usually err the complete opposite direction) or selling them in such a way as to minimize their sale price (settlement from a divorce, to spite someone, etc). The seller's inability to provide tracking information (possibly because they put 31 HGE replica coins in a #10 envelope with 98 cents of USPS postage on it and no delivery confirmation... I'm just guessing here...) makes this an open and shut case for eBay's Buyer Protection department.