I think they didn't like their tent. It was in very poor condition, they always had to "mend" it (Zina's diary) or "sew" it (unknown diary). The tent was at least once the occasion of a serious argument : "so they had a long argument, of who will sew the tent. Finally K. Tibo gave up and took a needle. Lyuda remained seated. And we sewed the hole (and there were so many that there was enough work for all except two attendants and Lyuda. Guys are terribly outraged." Nikolay was a punished, and as part of his punishment was to sew the tent... And there is only one photo where the tent seems to be the main subject (Slobodin's frame 26).
If for any reason one of the hikers was secretly smoldering anger and rage, the tent could have been a target at the day of wrath. For example : if there was another crack in the tissue during the night and someone was appointed to sew... We can imagine: "- Get up and fix the problem ! - Why me ? - Do it ! - But I'll have to go outside, and I can't do it by myself, we need to be at least two ! - Then another will go with you ! - No, I won't go." So two of the hikers prepare to go outside, get shoes and clothes, but they continue to argue and accuse the one who refused to get up, and at that point, for him, it's too much, all accumulated resentment surges, he cuts the tent. Then there is a first fight, chaos, screams. Some flee the scene. Then they calm down a bit and they join the others at the cedar. At first hey try to organize themselves. But some die of hypothermia, fight starts again and others are murdered...
I made a table summarizing all tensions mentioned in available documents (between two individuals and between an individual and the group), and all symptoms of degradation of social abilities amongst the hikers. The result is quite interesting but I don't know how to upload a table. Cutting the tent and giving up the group is the same thing, and several individuals had at least one issue with the group (Dyatlov, Dubinina, Thibeaux, Krivonischenko, Kolevatov...). And as typical materialistic soviets, they always repaired the tent, but never repaired any relationship... there are testimonies of: quarrel, rudeness, cursing, argument, conflict, and even double bind (or "paradoxal injonction", see Gregory Bateson), frustration... in the documents, but not a single testimony of a reconciliation and forgiveness.
PS : So cutting the tent from the inside could relate to the well-known phenomenon of "school shooting" which is so common in the USA.