Unlocking an Iphone-Phone and number was removed from account

I bought an Iphone 8 plus from a family friend.  He still has an account with AT&T and he just wanted to get rid of an extra phone he had on the account that he no longer uses.  He called the *611 number and had them cancel the phone number associated with the phone.  The woman told him that he didn't need to pay the balance at that exact minute on the phone and that the remaining balance of the phone would be charged to the next bill. (since he still has a phone with them).  The woman also told him that I would be able to apply for a request to unlock the phone within 48 hours.  And the fact that he didn't pay the phone off that exact minute over the phone did not matter and it would not affect me applying for the phone to be unlocked.  Now, over 48 hours later, the request to unlock my phone is being denied because there is a balance on the account (which there will be because he still has a contact and they woman said he could wait until the bill comes to pay it off.) I have less than 2 weeks to get this phone unlocked before I have to take my loaner phone back to Apple.  The phone and number have been disconnected from the account.  This should not affect me trying to unlock the phone.  I am now half a state away from the account owner and now I have to call him up and ask him to shell out money sooner than he expected? Is there another way?  I need this phone unlocked ASAP.