Passenger B may not have much hope, given that it's Air Asia he's dealing with. He'll have to judge whether the time and effort spent fighting the battle to get that sale fare/reservation re-instated is worth it, versus the cost of buying a new ticket on another carrier on his own. I would imagine this would take a supervisor, not the usual phone flunky. Sucks, but Passenger A should not have cancelled (his) reservation until the resolution of the service disruption and Air Asia rebooking of both of them onto an alternate flight had been done. Too many simultaneous moving parts in this situation.