At least one of the hikers climbed 20 feet in the cedar tree. I do not believe he was doing this to gather firewood. He was most likely climbing the tree to either get away from something. Or possibly gaining a better view to look back toward the tent to see if the threat was still there.
Whomever climbed the tree did so to look at something. Nearly all of the investigators emphasized how difficult it was to break the branches and that the branches were broken specifically to clear a window to gain visibility to something. Since the window was cleared on the side of the cedar facing the tent, there is a possibility that the person(s) was trying to gain visibility of either the tent or the slope. In M. Sharvin's interview he said:
"For a fire, no one will climb to such a height to break off branches for a fire, when branches remained lower; the same trunk was two and a half meters bare, that is, it was broken off. Then, a row of branches. And already much higher, branches for this window are broken. I.e. it is obvious that it was used for surveillance. Nothing else could be seen from there. It turns out, most likely, I am inclined to the fact that it was one of them who made the observation window. Someone could have had enough strength. I don't think it was an outsider, it seems to me - no ... But who could have remained so strong? Only Kolevatov, maybe?"
To me it doesn't make sense to climb a tree and look back at the tent if they were led to the cedar by a third party.
I simply do not believe that infrasound caused this event. (mainly because of the hiker's injuries)
Again, infrasound was not
responsible for the injuries at the ravine. Instead, they were caused by a fall. I don't agree with the infrasound theory, but I think the fall into the ravine (despite it's problems) is the most likely scenario for the injuries at the ravine. A fall is a perfect example of Occam's Razor.
I highly recommend reading Donnie Eichar's book 'Dead Mountain' that thoroughly details the infrasound theory.