It is hard to say without further information. I'm far from an expert in desert survival, but I would imagine the 115-118 degree heat they were mentioning to be the same kind of exposure hazard that subzero temps up here in the north bring, ie just being outside is a survival situation, and you need planning, safety, and emergency gear for just about all outdoor activities. He is described as an "experienced" outdoorsman, but if so, he seems to have pushed risk over the edge. In anycase, RIP.