i have done a very similar route to this also getting my d's confused it wasn't wet and i'm not sure about the last pitch but up to the cave with loose rock's it sounds very familiar. i also remember a steep corner with a hand crack somewhere towards the top. my second still claims that it was the hardest and scariest thing he has ever climbed.
i agree awsome line. strongly suspect it would have been climbed previously either by others making the same mistake or deliberately because it struck me as a reasonably logical line. i assume you have "selected climbs" like me and i think i could pick most of it as parts of other climbs given the wonderful benefit of hindsight. if you could find a comprehensive guide i reckon there would be a fair chance it would be in there.