eBay buyer issue

[HOF Auto Rookies]

I know this is not the right section, but I didn't know where to post it. I sold an autographed 2009 Bowman Chrome Mike Trout card. Here's the link http://cgi.ebay.com/ws/eBayISAPI.dll...:X:AAQ:US:1123

Seller receives it stating this:

"Was looking forward to getting this card in the mail because it was supposed to be GEM MINT as you say. Well I got it in today and lets just say I am not too happy. Card is way off centered which because your picture is blurry you cant quite tell in your auction and it also have several other surface flaws. I will be sending it back for a full refund. ThanksMike"

Yeah the pic sucks as it was taken with my phone, but clearly you can see their is no major centering issues. Way off!? You kidding me? Top to bottom it's BARELY off. What can I do here, this is just ridiculous. I did not notice ANY surface issues.

I think he's just pissed because he significantly overpaid on this card.

What can I do here?