I could be wrong, but I thought with a few of them, their cell phone was found, just at an odd place or whatever. I could be wrong though.
Several of them did make phone calls that night. Some attempted phone calls and got voice mails etc too.
SS.....I guess one of the commone denominators of these is the speed with which the various LE agencies are quick to dismiss these as ALL accidental. Just like if you want to get away with murdering your wife, you make her disappear so they don't know WITHOUT A DOUBT she's dead. Just say she left you for another man, ie DPeterson, Stebic, yadda, yadda, yadda.
Kill someone who's out drinking, either make them completely disappear without a trace or drown them, and it immediately becomes an accident.
The perfect crime, I would say.
JMHO
fran