I don't know about his capabilities, but looking at
his resume he was previously an instructor in Jungle Survival for Navy Special Warfare (NSW) command. And he spent significant time in Iraq where he conducted "multiple successful high risk missions", so presumably he has familiarity with harsh desert environments.
Obviously, we don't know what actually happened. Maybe there was nothing he could do to save himself or FJ, and I don't want to cast aspersions when so much is unknown. But his background and experience just adds to the overall mystery of this case.