Responding to: "The cuts are strange in and of themselves because they run more horizontally than vertically."
They may have tried to cut horizontally first but couldn't get enough force that way, due to the small size of the tent (can't stand up). If you are kneeling and use two hands on the knife, I think you can cut with a lot more force if you do so vertically (starting as high as you can and pushing down). The idea to cut horizontally may have beeen due to how the heavy snow/ice had formed, if they did try to cut that way first.
I'll also mention that most items they took with them to that site were found positioned in a neat/orderly way, and this suggests they acted quickly and thought those items would be reasonably well preserved in place. The idea that this was stage is far-fetched, to put it nicely, but regardless, you go with the evidence you have, or else you are "assuming facts not in evidence," and so should be working on obtaining that evidence, rather than suggesting the actual evidence has been faked. It's not as easy to fake crime scenes, say a husband killing his wife in a house that they share (with nobody else living there), so the idea that this type of scene, which is consistent with simple bad decision-making in a hostile environment, should be tossed aside is just ridiculous (to those who are making such claims). But I welcome attempts at reconstructing all or part of the incident, as that always seems to lead to new or interesting revelations.