IMO, I don’t think she went missing voluntarily. I think she went exactly where she entered for Lyft to take her early that morning. Not to be disrespectful at all but maybe the destination was to a sketchy place where she’d been before and for that reason she didn't tell her roommates, friends or family that she goes there?
And maybe she didn’t go missing when she first arrived at that destination, but perhaps it was later during the ride back home (or to wherever) from that destination?
Just my opinion
I am thinking the same thing, or something happened right when she got there. Jmo.