Jason, please accept my condolences for your loss. Steve's post expresses how we all feel better that I could have said it.
Steve's description of the North Slope is accurate. I just want to add a bit of information to what he said. My guidebooks rate it class 2-3 in difficulty (where 1 is walking on a trail and 5 is technical roped climbing). I climbed it in September 2002 on my way from Mt. Russell to Mt. Muir and back to Mt. Whitney. There are several black water stains on the rock in saltydog's photo, and I probably went up near or to the left of the leftmost water stain. There wasn't much snow, but I found a lot of loose rock. I thought the route I chose was more like class 3 and 4, though there are probably easier ways up. Much of that slope is rotten rock, making it fairly dangerous and unpleasant. As Steve said, a tiny mistake could lead to disaster.
Jason, you've invited us to say what we think could have happened, and I'm going to guess that fatigue and altitude led your dad to try a "shortcut" back to camp that didn't work out. I won't speculate on where your dad was found. The authorities can give you more accurate information than I can.
I wish you and your family well.
