First off, Great Photo (in my opinion).
Judging by what I've seen so far from Adobe, they may have a piece of software that does an initial screening of the image rather than an actual person (due to high volume uploads). I'd assume the black shadows do have some noise, which I'd expect in that level of darkness, but the program may have read the texture in the rock as noise as well.
This is all a guess, but maybe delete it and try uploading again. It's been a while and maybe the program has had some good updates since or maybe you'll get a reviewer that appreciates the great pic it is.
Great photo. Cannot see the problem. If I was to critique then the two blown out steps could do with some work.