I don't know that I believe that Steven ended it all, but it would be possible that his body isn't found for a long time if that is indeed the case. Several years ago I was on search and rescue in southern Utah and was looking for a gentleman who had left messages to the effect that he was going to commit suicide. We found his car parked in a scenic lookout off of a state highway. We searched extensively with dogs, helicopters, fixed-wing planes and hundreds of searchers in a grid pattern. We put in thousands of man hours over the course of several weeks and never found him. He is still missing some ten years later.
A few years ago, a friend of mine
http://www.theyaremissed.org/ncma/gallery/ncmaprofile_all.php?A200503734S left his truck parked in the area of the Valley of Fire, wandered away and hasn't been seen since. He was older and suffering from health problems and the early signs of dementia. His family thinks he simply wandered off and succumbed to the elements. They searched and searched over the course of months and haven't found any sign of him.
Improbable as it seems, if Steven got in to trouble in the desert or harmed himself, he may not be found for years if ever.