It seems probable to me that the bodies of the ravine4 and the two Yuris were moved after death and "positioned." Maybe also Igor's body.
Therefore, I am starting to divorce the two Yuris' deaths from the cedar tree. I don't know if they had anything to do with the cedar at all, aside from being positioned at its base after their deaths. Is there really evidence that one or both them climbed the tree? Fell from the tree? Cut a window of branches so they could watch the tent? How about being burnt in the little campfire that was not well-tended and only burned for 90 minutes? I am moving them away from the cedar and looking at other possibilities.
Same with the 4 in the ravine. Their injuries killed them quickly, so it's possible they died elsewhere, were brought to the ravine after death and positioned.
Hopefully, thinking like this can open up more options for what happened, instead of binding my thinking to the cedar and some kind of snow dump at the ravine.