I suspect the right thing to do is give the guy his money back, but only because I almost always choose to take the high road, and generally, I do not fight for anything in this short life. But if the roles were reversed, I would call myself an idiot and not expect anything back for wasting someone's valuable time.
I should ask this on my motorbike racing forum. Those guys are hardcore. I suspect they would not be as nice and understanding as this group
