You can play your wifes and your friend who quit playing no problem. Just pay him in advance and let him reactivate it. If he isn't willing to do this then don't use it. Although different billing vs account information won't get you noticed automatically, if you were to ever get reported on the accuont they could end up looking at the information. When that happens, the worst case is they lock the account and require him to send in his valid photo ID.

Bottom line;
Have him pay for it, pay him in advance (or whatever you want to do) and play away. You won't have any problems, as long as you both don't log into the account from locations that are far away.

-S