I am skeptical it would be that man's kayak, but nothing is impossible. That kayak was pretty far up. I walked up there, and the sand was hard to walk in and there were tons of thorny bushes tearing into my legs if I mis stepped. It would have been miserable for two people to carry a kayak that far up. It would have been very difficult to one person especially an older person. In 2022 I kayaked from Antelope Point Marina in Lake Powell into antelope canyon. The water level was so low that we had to carry down the kayaks some distance to get to the water. Carrying the kayaks back up on return was miserable and difficult and it was two of us. That kayak was much higher than we had to carry ours. To me it looks like that kayak was anchored when the water level was much higher and left in the elements. If he carried his kayak up that high up from the water, then why did he tie it off on a rock?