I dont understand how Paypal can not side with you when you provided proof of delivery. I thought Paypal would have absorbed the error...because after all Paypal was the one who got scammed...and you do pay fees for using their system. You need an ID to open a PObox. I would call the place where his box is and report that someone is using it to commit mail fraud. You can easily email them all the proof. Plus he is importing a lazor. You must get the law involved because he has committed many high crimes.
Good luck.
Good luck.