This topic is interesting because I experienced a related situation.
I recently purchased some cables listed here. When I clicked the 'buy it now' button, it directed me to the paypal site as expected. I submitted my payment and didn't think more about it.
I reviewed the payment receipt shortly after and noticed that it listed not my address by default but some random address elsewhere! I panicked and quickly was able to update the shipping address within minutes of paying for the cables. Everything was fine.
While your situation is unfortunate, assuring everything is correct on your end is your ultimate responsibility. I always triple check PP addresses and other other info before transacting. You might have some recourse if Agon will step in but it seems like this your negligence sadly. Good luck.
BTW, I find your reference to the guy's ethnicity offensive. Everyone is capable of lying. The fact the guy is Chinese is irrelevant. He's just a guy who may/may not be lying. Your claim is just conjecture. Are you lying??? 😮