I also wanted to add that you can call paypal and talk to a rep there.
They will assist you in how to proceed with proof you have and the fact
that one of these people has been associated with scams previously. Tell
them everything you know.
I had a chargeback in the past for someone claiming their cc was used
without authorization. I sent proof of shipment for the item to paypal
and they ruled in my favor. Send them the info they request and hope all
goes well.
