For the T&C: When I questioned about this some years ago (twice) - this was pointed out to me "2.7 The Member must actually travel to gain XP and earn Miles. XP and Miles will not be awarded on unused, forfeited, fraudulent, lost, out-of-date or refunded tickets. The Member can gain XP and earn Miles only for the flight flown, even if the Member purchases tickets for other people or purchases several seats on the same flight. On Air France and KLM operated flights a Member can earn Miles when booking an extra (paid) seat, including but not limited to a stretcher or transportation of fragile oversize baggage in cabin, provided the extra seat is booked under the same name as the Member and in the same booking class as the Member’s own seat. In the event of a transfer onto an alternative flight due to circumstances unforeseen (and not caused by the Member) the Member will gain XP and earn Miles for the flight originally purchased, and not for the route flown. Miles are earned on services and, or extra options only if personally utilised by the Member. The Member’s account can be credited only once for each flight flown and can be credited only once for each service used. The amount of Miles assigned will be based on the Member’s level at the time of each flight flown."

The bolded line is what was informed to me - in my case, I was always rerouted by LH/LX to KLM. I suspect this was the case too above, as I don't think ever other airline ticket stock (when not partnering with AF/KLM flights) will issue it on KL/AF/ST airlines - means that this was due to a rebooking.

Therefore, if the person was booked originally on a non-FB partner, the T&C indicates that the OP needs to request LH/LX or which *A partner to credit his/her *A program - as it will not work for FB.

Cheers!