I wish to hell I had a Miss Marple or a Hercule Poirot next to me for this one. Preferably Poirot....this case seems more up his ally.
First of all I have a bone to pick with LC - I don't believe the snow den was a fake! Whether the actual site was staged or not, I think the hikers did create that thatch of branches and it was to play some role in a shelter for them. I'm willing to concede the searchers may have staged the actual spot, but I believe it was at least part of some of the hikers' plans, successfully executed or not. I believe I even saw a quote on here from one of the searchers saying years afterward....the bodies and snow den were right next to each other, not meters apart as has been claimed in other places. I've seen pictures that dispute this as well....bodies seem to be a max 3-4 feet from the supposed snow den site, two holes in the snow right next to each other. If it was right on the river/stream....easy enough for them to have started off there and then melted downstream a couple feet in a couple months as things are melting and water is flowing.
I've read your 'exact spot' argument before....not sure why the searches couldn't/wouldn't have shaped the hole as they went down using their meat hooks to see where something was. The hole may not have started off in the exact right spot/shape but they easily could have developed that as they were digging down. It takes time/effort to dig a hole like that...I'm sure they were sounding it out as they went and shaping their efforts from there....hence why the final product looks 'too perfect.'
So...long story short the snow den WAS a thing for the hikers, whether the searchers uncovered it exactly right or not. I'd go so far as to say there was a den, and the ravine four were 'in' it when they died. Melting and stream effects pushed them a little downstream from it.
Everything that happens can pretty easily be explained in a very stupid, pathetic, calamitous series of unfortunate events. It'd have to be quite a coincidental string of awful events but possible....except there's the extraordinary event of them leaving the tent in the first place which is very, very difficult to explain (IMO, and I'm sure many others). Pretty obviously the sequence of pathetic, calamitous events has to be connected to the initial extraordinary event - chance and coincidence only extend so far. If you accept the deaths of the hikers as unfortunate fate, that fate can only be extrinsically intertwined with the initial catalyst or your asking for too much coincidence in one place. I rule out infrasound, avalanche, and katabatic winds for this reason. Any one of them can POSSIBLY explain the initial abandoning of the tent, but I don't see how any of them or even any combination of them could also naturally result in the ensuing helter-skelter.
When I channel dear old Agatha, she tells me the crux of the solution lies in the differing states of undress of the hikers. All of them were under-dressed. Some of them were more so than the others (even before their corpses were stripped and looted). I think establishing the exact initial state of each hikers' clothing situation would be very instructive on how events played out. Considering the absolute necessity of proper attire for survival...the fact that any of them were under-dressed is telling. The fact that all of them apparently started out in extremely varied states of dress/undress....I feel that somehow has to be determinative. Just haven't figured out how yet. ;)
The yeti photo was clearly one of them doing a riff off the recurring joke in the Otorten newsletter.
The photos in Symeon's camera were ruined, not extraterrestrials or bombs or....your mom.
While the two Yuris almost certainly died before the Ravine 4....that's not a given. Never trust anything you hear. It seems most likely, but it isn't necessary from any data we have so far. The 3 on the slope....might have all been coming, might have all been going, or might be some mixture thereof. Doesn't help you to get stuck in any mode of thought on that.
Another very critical factor (very difficult to establish) is when did this event start? Were they just setting up camp? Already in for the night? Was the food in their stomachs found by the coroner lunch or dinner?
I dunno I guess that's all I have for now. Main take-aways: the snow den did exist; and if we knew exactly what state of dress and what time of day/where in their routine they were when the event happened, I think we could deduce the sequence of events from that.