I’ll be the lone voice to support the seller. Just as many say you should verify shipping address, as buyer I ALWAYS independently provide seller with my shipping address. Everyone should do that.
Because this looks like a scam, he is correct in allowing AG/PP to research and advise. Even though the seller has been paid, a scammer knows he has perfect rating and will reimburse one buyer eventually. Or AG or PP will.
I suggest the seller stay the course. Something is fishy here and I suspect the scammer wins only once he receives the returned payment.