i think that a big avalanche was headed towards the people and thats what cause them to panic and also what knocks down the trees. they all die when the avalanche hits the cabin and the window breaks and an avalanche doesnt leave footprints. i pretty much got this puzzle solved. at least i think i do.
jeasus no nature of forces caused this and this happen and everyone died hitting something no earthquake thats a force of nature and the anser is jsut like 3 words long.