For how much they were lamenting the situation I'm a little surprised nobody ever once suggested that they just take the easy trail in spite of what they wrote on their paperwork. Maybe somewhere off-page they brought it up with the teacher and got shot down.
"Yeah I know your group's made up of some no-life homebodies, a forgetful nebbish, and a girl who's so borderline emaciated she can't even jump for a photo op, but your sign-up sheet says you're hiking up the Murder Trail on Devil Mountain, so up you go. Be back at the bus by nightfall, and if you run into trouble don't bother calling for help; up there only the gods can hear you, and the laws of man hold no sway."