We can not rule out fear to explain their evacuation of the tent. All behavior is motivated. I can imagine a fierce snowstorm that splits the side of the tent. As snow pours into the tent, the hikers scramble over each other to get out.No time for boots! In the congestion inside, they fear entrapment, crush and suffocation. It would not be easy to sew the tent back up in a hurricane wind.It would not be practical to shore up the torn wall with hand packed snow against the cold scouring wind.
Any port in a storm! They make for the forest and make a quick assessment Breathing, Bleeding, Broken Bones, Burns. Each is attended to as well as possible, but eash was inadequate under the conditions.
The elephant in the room is why their corpses were checked for radiation. It occurs to me that the test was done at the University, not the hospital. In that case, someone thought it a good idea to be thorough. After all they did keep the ruined tent, yes?