On award tickets, does the credit card used to pay for the taxes need to match the person's account? That might be the only problem I can see on the booking pretending you are your dad. My sister died 5 months ago from cancer & on the transfer of Hilton points, the credit card name had to match the account holder's name. Not sure that applies but something to check into. I'd go w/ Option A myself, as it's the easiest & your dad is willing to do it, or Option B. Sorry to hear about your father's condition.

Cheers.