I think the whole timeline thing is literally just referencing save files…because to Dave, not knowing how he remembers passwords but still getting them is just us, the player being Dave in different saves files with knowledge from a different one.
Also we’ll just hafta see, but Dave being in a relationship or not isn’t exactly mandatory when it comes to getting of the mountain in the end…routes in this game (and pretty much everywhere) are kinda there for perspective building, but there’s always an overall story to tell :)