I still give fair odds that the guys caught a ride to a casino and have been dead drunk and knee deep in hookers spending their kids inheritance. That in a few days they will come stumbling out of the desert, suspiciously well fed and watered, and tell some miraculous tale of being led in a strange mist to a tiny hidden spring by the ghost of an indian, or an alien abduction.

That, or they realize that it has been too long and they quietly, grow beards and relocate under an assumed name into a quiet mountain town where people don't ask to many questions.

Or some hiker finds a set of bones in a year or two.