In my opinion, they may have simply needed dry firewood. In these conditions, everything on the ground is water-logged and subsequently frozen. It makes more sense to collect dry dead branches still attached to a tree. After you have a good bed of hot coals, it's possible to thaw and dry wood from the ground, but they didn't get that far. No, they HAD to have dry wood still attached to a tree to have any chance of getting a fire going.
This is like camping 101.
It is possible that they could have scrambled up the tree in desperation even to get fire wood. If they were freezing to death and the only dry fire wood was on the cedar then the wood becomes a matter of life and death?
I think the cedar is worth considering in more detail to understand it objectively in the context of this particular theory.
Here is something to think about and worth discussing:
Would you agree that there is a fair amount of evidence that Yuris D climbed the cedar? - moss and pine needles in his hair, cuts, bruises and abrasions on his body and particularly around arm pits. It's unlikely that he got those abrasions and bruises in those locations while descending the slope?
Now, we don't know exactly who was at the cedar and when. Yuris D and Yuris K were there. Some of the other group members may have been there earlier on, or not until later when the clothes were removed.
What we do know however, is that not everybody would "need" to climb the tree to collect the dry wood. It would only take one person to climb, and break down the branches and throw them to the ground.
We also know from the autopsy reports that Yuris D had severe frost bite on his fingers and toes. So much so that it is said that if he had survived he would have needed his toes and fingers amputated.
So the first question: did Yuris D sustain the severe frost bite before or after the fire was lit?
Probably before? If the fire was lit before the frost bite then he shouldn't really have gotten the frost bite.
But if he had severe frost bite before the fire was lit then he probably wasn't the best choice of person to collect fire wood from the cedar. So why would he climb the tree?
If he and Yuris K were the only ones at the cedar then Yuri K would be better placed to climb the tree and pull the dry wood down? If there were other members of the group there then most of them would be more capable of climbing and collecting the wood. But for some reason Yuri D still climbed the tree with frost bitten fingers and toes so severe that they would require amputation?
Or was there another reason for climbing the tree with severely frost bitten fingers and toes?
Are there any other explanations?