I wonder if he's playing for time and shifting money out of his bank account and or closing it. PayPal will put a hold on the funds as soon as you make a claim, but if the money has already gone to his bank and he then closes it, Paypal NEVER foot the bill... They may put his account into a negative balance, they may not... Hopefully the former for you.
It could be simply he's spent some all. Of it and trying to get some time until he refunds you...
When is the date he has to officially respond by?
Did you pay via a PayPal balance or via credit card or attached bank account?
I'm still very confident you will receive your refund... But always pay the fees especially for something so expensive, you really wouldn't have had much chance of a refund if you had paid via gift... Only if paid via an attached credit card and you brought your CC company into it with a chargeback, still sketchy then.