I’d buy that. Sound or snow hitting the tent panics the group and, blindly, trying to get out they slash the tent. Some are half clothed, others not. They flee, stumble or are taken down in a snow slide and suffer injuries on rocks or just being tumbled. Some die quickly. Some regroup and try to find shelter in the bitter cold night and die of hypothermia in fairly short order. One, the woman, lies dead out in the cold on the surface or near to it. Later, birds find her corpse and feed on the eyes and protruding tongue.
As an aside, I can assure anyone that has never slept at altitude or in sub-zero conditions that being in a mummy bag and crammed like sardines in a tent is a good ingredient for the panic that can ensue from clostrophobia, the absolute stygian blackness or the sounds that cannot be identified or that can be such as the roar of snow moving at speed or even the cracking of ice beneath you on a frozen lake (sounds like cables under tension being plucked).
Seems to fit the facts for me but I don’t believe in aliens, either.
// Later, birds find her corpse and feed on the eyes and protruding tongue. //
except that a comment above notes that, apparently, blood was found in her stomach from trauma prior to death.
interesting aside, btw :-) — trumps trees twisting in hurricane winds around a house, I bet.