Is it obligatory for someone who took out a loan in his friend's name to repay the remainder of it after the company waived it, and is it permissible for the owner of the loan to accept that?

The person in whose name the advance was issued is the debtor to the company, and the pardon issued by the company covers the original debtor. If the original debtor chooses to waive his friend's debt, that is good. If he demands it, it is his right, because the Prophet, peace and blessings be upon him, said: "The hand is responsible for what it takes until it returns it."