It doesn’t strike me as automatically neglectful or nefarious that her friends left her. It’s likely that she initially intended to drive home, so that’s what she told her mom. She might not have expected to get drunk so fast, but maybe she had been “pregaming” beforehand. Then realized at the party that she had become too intoxicated, and decided to sleep it off.
Her friends might have actually thought that was the safer decision for her.
Maybe most of the unfamiliar people seemed to have left by the time they did, and most who were staying to camp were local.
Maybe her friends left her with a group of people they knew and felt comfortable with, but can’t mention publicly because those people are being looked at by LE.
Maybe she hadn’t charged her phone long enough earlier, and she passed out before plugging it back in so it died. And maybe she fell asleep with her car doors unlocked.
It would be interesting to know how many people stayed behind to camp, and how far away her car was parked from other people. Was she tucked away in an isolated spot that seemed safe because she was hidden, but being out of sight from the crowd made her a vulnerable target? Or was she parked in a crowded area that felt safer than being alone — but was also full of potentially dangerous strangers — and campers were asleep or too drunk to notice anything unusual?
When I was 16/17, if I had attended a party in the woods and decided to sleep in my car, my friends wouldn’t have batted an eye. They knew I was a competent and experienced mountain girl who’s as accustomed to sleeping on dirt as I am to driving on it. And if were intoxicated, they would’ve been relieved I wasn’t trying to drive. But their own parents wouldn’t have allowed it, so they wouldn’t have stayed behind themselves.
Her friends know her and might also consider her fairly capable. Most are probably pretty comfortable campers themselves, especially in an area they know. At that age — and inebriated — we know teenagers often have an unreasonable sense of invincibility.
I think I remember an earlier comment that even though her home was only 12 miles away, it was a 30+ minute drive. That might sound daunting to an exhausted and inexperienced teenage driver, no matter how familiar she is with the roads.