Not quite. It would have been much easier if he unlocked the phone while it was still with him before selling it. He should be willing to cooperate first place. And you should have been more careful when buying it, but things cannot change now, so you just deal with the situation whatever it is now.
It doesn't matter where he uses the phone or what SIM is inside. Verizon should be able to provide the right unlock code. He needs to tell them he wants to use the phone with foreign SIM outside USA and needs an unlock code. Given the fact he has good account and with VZW, they will give them the codes.
He can always make up a story relative of him is in Europe and wants to have phone unlocked and he is calling because phone is activated on his account, but phone isn't with him at the moment, this still should be fine. There is no logical reason for them to refuse to provide the codes. I am saying codes as it could be up to 3 codes they have filed per handset. He must try to get all them for you to try.
If things do not work out, based on how he had listing put together, you may be eligible to reverse the transaction and get your money back. Since it is your problem now, do not leave an option unresearched.
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