In reply to MarkH55:
My mate and I actually bumped into this guy and his daughter at Biblins a couple of weeks ago when he was trying to film this. We turned up on a weekday evening at about 4pm, and were asked to climb elsewhere for an hour while he did this piece and lit a fire (!). We pointed out there was nowhere else to climb, we would happily share the cave but it wasn't reasonable for him to reserve the entire thing, and also that he 100% shouldn't have a fire there as it's part of an SSSI, with fragile access for climbers as a result.
To cut a long story short an argument ensued, he threw a bit of a tantrum and then left. Funnily enough, his teenage daughter was much more mature and understanding than he was and looked mortified. We dismantled his unlit fire but I guess he came back again at some point to film this...
Tbh, the whole thing epitomised why I much prefer the climbing to the mtb scene.