[mothered]

Why would it? He told me he's not using it anymore that's why he wants to sell it.

His Intention Is Immaterial.

It's associated to his credentials, so It's quite obvious your SE will Involve him In some capacity.

If not for individual sellers, how would I obtain the POP  and SN?

Purchase the product from a company on a large scale, take note of the serial number and keep the POP, then return It for a legit refund. Alternatively, use the corrupted file method for the POP.