As the Head of Training of Bloggs' new Flying School will have to sign a Course Completion Certificate, he will have to be presented with convincing evidence that the training took place for it to count.
An RAF Flying Scholarship should be certified in the pilot's logbook by the CFI of the Flying School concerned, and his original training record might even still exist.
If neither of these are available, it should be possible to confirm the completion of the Flying Scholarship from the records kept by HQAC.
In any case there is no time limit on the validity of flying training, and, so long as evidence can be produced, it will still count.
MJ