No, we didn't sign the register. We passed only one hiker on the way back from the summit as our bubble proceeded forward.
At the risk of rote speculation, I now think I know who the fallen hiker was. If it's the person I think it is, he started the Chute with me and BlueWater. If you go back to the conditions report (http://www.whitneyzone.com/wz/ubbthreads.php/topics/53051
), you can see him in the photos. He had two ice axes, and he was using them to climb the Chute like an ice waterfall ie holding the handles and swinging the pick axe heads into the snow.
We both remarked he had a heavy coat, no backpack and no noticeable means of carrying water. (Look at BW's remarks here: http://www.highsierratopix.com/community/viewtopic.php?f=1&t=18106&start=10
If it's him, he's in 3 or 4 photos). I thought he had turned around at the Crest, but BW said he had carried on to the peak. We never passed him on the way back, and we never saw him again.