Mystery Yuba County Five ("American Dyatlov Pass")

[LicoriceAllsorts]

https://en.wikipedia.org/wiki/Disappearance_of_Gary_Mathias

On the night of February 24, 1978, a group of five young men from Yuba City, California, United States, all with mild mental or psychiatric issues, attended a college basketball game played at California State University, Chico. Afterwards, they stopped at a local market for snacks and drinks. Four of them - Bill Sterling, age 29 Jack Huett, age 24, Ted Weiher, age 32, and Jack Madruga, age 30 - were later found dead; the fifth one, Gary Mathias, age 25[1] - vanished, and has never been seen again.

Thoughts on why they would go completely out of their way, and in particular what happened to Mathias? I think it might have been a team bonding session gone wrong the night before their basketball tournament

The five men are known collectively as the Yuba County Five, and the incident itself is referred to as the "American Dyatlov Pass." Police in the area continue to investigate.