Has anyone here had success with booking an IAP fare for someone where the primary card member is not traveling? When booking for a family member, I can change the passenger details from mines, to the family member. But not sure if this will be an issue down the line, so wanted to see if anyone else has done this online?

I did read that I could add the family member as an AU, but there is only one ticket left and I can't wait for the card to be delivered.