So still no takers so I suspect that either......
Its too fiendishly clever
(but its the same construct I've used before), or
I've made a cock up in the anagram bit
(though I've double checked and don't think there is), or
Its too obscure a cave
(though it even merits a photo in Sam and Beardy's new tome so can't be THAT obscure).
So there's some more clues in there. Anyone?