The cedar tree was being used a central hub to stockpile tree clippings and clothing to make the snow den. Or, at least, that was the impression that the first searchers at the scene got. And so the tourists would be coming and going, not just to get supplies or drop them off, but also to sit by the fire and warm themselves up. Considering they were trying to dig out a snow den with their bare hands, in frigid temperatures, many of them underdressed, they would have needed frequent breaks to stave off hypothermia.
So I think what happened is Dyatlov told Yuri and Yurkin to tend the fire and keep an eye on the tent, or at least keep an eye on the direction where the tent was, while the rest would make the snow den. The two men look like they fell out of the tree, and that’s probably what happened. For instance, maybe one of them fell asleep through sheer exhaustion and the other one tried to save him, but lost his balance as well.
Between a nasty fall and frigid temperatures they didn’t have the strength to get back up. Perhaps, they hoped one of the others would come back and eventually, someone did, but it was already too late.
Obviously, after the other three hikers were badly injured, Dyatlov must have realized that they needed to return to the tent and brave whatever danger was there. He helped transport the injured to the snow den, left them in Kolevatov’s care, and returned to the campfire to cut the shirt off Yurkin, rolling him over the process. Then he, Zina, and Slobodin began their ill-fated trek back toward the tent.
Meanwhile, Kolevatov could have gathered up the other garments from the deceased to place on the floor of the den, and dress Luda with. Tragically, though, it didn’t matter. Dyatlov never came back.
Admittedly, that’s a lot of suppositions. However, I was trying to come up with a scenario that reasonably fit the known facts.