In the Google earth map it looks like they have the "Upper Mic" in the wrong place. It should be one ridge to the West right on the dot there.
I agree with B87----my best guess would be he was headed to the back of Nualolo, was prolly hugging the ground with a cloud bank on his right, slowly getting worse and then realized it was not going to happen and tried to get back to the canyon. Had he have been going West he would have been OK I suspect.
That sloping plateau from the back of the Canyon to the coast is very deceiving, there are few distinguishing features, and it is easy to get disorientated, especially as one rarely looks at your compass. I have to admit, that I once was doing the exact same thing, saw an opening and announced to my passengers that the Napali coast would appear out the right window in 5..4..3..2..1..... and.... never mind, we are back in the canyon again. That is how easy it is to get dis-orientated up there.