AFAIK, Ebay no longer requires the seller to pay for your shipping costs to return the fake to them. Again, someone correct me if I'm wrong.
And of course, Ebay is going to fudge when they say there was a violation but don't say what kind - the fewer fakes being returned for refunds, the more money Ebay gets to keep.
WHATEVE said
"ETA: So it looks like they are saying it might be a fake, but if you already paid, it almost seems like they are encouraging you to keep it, rather than trying to stop the seller from shipping it"
Maybe they're hoping you'll RE-sell it on Ebay and they'll make even more money from the outrageous Ebay and Paypal fees!