I wonder if the eBay seller is a drop shipper who is simply selling things they order themselves via Amazon (But ship to the eBay buyers address)? They make a slim profit of each purchase and hope they can “sell” enough volume to make it worthwhile. Did the amazon branded padded envelope look new (or was it clear someone simply rewrapped an old amazon envelope)? If it was a new envelope then I’m pretty sure the eBay seller simply ordered something off amazon and had it shipped directly to you.
Whatever the case, I’m sorry you have to waste your time dealing with a bad seller.
Whatever the case, I’m sorry you have to waste your time dealing with a bad seller.