The only circumstance where someone 'has' to travel that I'm aware of is if someone booked using an Avios (air miles) companion voucher (nicknamed a 2-4-1), where the booker needs to fly with the companion.
However, for full reassurance I would turn to the experts on FlyerTalk's BA forum -
https://www.flyertalk.com/forum/brit...tive-club-446/ - after having a quick look to see if your situation has already been covered adequately already.