Oh dear.
When we signed people in at Cadwell for TA2 earlier this year, there was a lady from the circuit checking licences, which was something that had not been done at Mallory. I believe it is the circuit operator that requires sight of a licence, not the trackday organiser, probably something to do with insurance.
One of the guys - never did find out his name - duly produced his licence, only for the lady to point out that he had no motorcycle entitlement, despite having ridden on the road for 30+ years
He wasn't allowed out on track, though fortunately his son used his bike instead.
The good news is, however, that the Cadwell people were prepared to ring DVLA for those people who had forgotten their licences and to take the DVLA's word. So you should be OK, but if I were you, I'd ring Cadwell circuit and explain the circumstances and make sure that they will do the same for you.
Hope this helps.