I am curious to know how closely GE is being watched by LE; I'd bet very very closely.
I suspect that LE is tracking her movements 24/7, either in black and whites or undercover. Bet her phone calls and pings are being monitored via a judge's order, as well. She has every reason to be very paranoid until LE arrests her or decides she's not a suspect.
I think it's possible [GE] lured Michelle out to the car under a false pretense, possibly using someone else's phone to text Michelle at work and pretending to be that other person. Why would Michelle need to make a quick run to her car in the midst of her work day? She clearly didn't expect to be gone for long at all; she left most personal belongings inside. I think she got a communication while working that lured her out to her car.
You might be right, but news reports have consistently stated that her fellow students said she was making a quick run to the car "to get something". Seems like she would just say she was meeting someone briefly instead...unless she didn't want to reveal who that person was, maybe.
Her pals could have missed a text or a phone call to her...but you know LE hasn't. Anyone who called or texted her within a short interval (or beyond) has been ID'ed and probably interviewed.
Are we sure this wasn't a random killing/abduction? Maybe LE shouldn't be so quick to deny that, but on the other hand, maybe they know something that makes it near certain that it isn't a stranger who is responsible.