Science tells us that only a gale force or higher can cause a raised footprint in the snow. There is a photo of the tent that shows a cut on the canvas of a half circle. This appears to be made by someone who is using their shoulder because they are lying on thier side, which points to a snow collapse, in nature, humans tend to cut horizontally and vertically. Once everybody was cut free, they found themselves back out in the gale force winds. They need shelter immediately, pronto, as fast as they can. Digging out extra clothing would take to much time so they decided very quickly to move to the forest and start a fire..Because of the continuous gale force winds, most of the snow on the tent blew away, erasing most of the snow evidence. There are only some many reasons to use a knife in thier situation alone...They were trapped...in my humble opinion.