Knowing how the accident happened is important, of course. But I don't think we will learn enough without Bryce being able to say what actually happened. It will all be guesswork, albeit maybe more-educated guess work, if more details are learned.
For me, the minute-by-minute details of what was going on with Bryce from Tuesday or so, is more vital as far as figuring out his mindset. I know we are not supposed to talk much about drugs, but I think they figure greatly into whatever happened to separate him from his vehicle and ultimately vanish. Someone knows where he was really headed and why, IMO. Someone knows why he may have been having emotional or other issues, causing him to blow off classes and not keep to his holiday plans.
Also, I don't like bringing up the idea of suicidal thoughts, but we have seen many cases of suicide here at Ws with much less drama in the hours before the person disappeared, than what we have heard here. It can't be ruled out, IMO, by saying "Bryce would never...". We can never know what a person is thinking or how close they are to a breaking point.
JMO