So there is no video of her or her friend's car leaving the parking garage, and no video of them driving on any of the streets around the garage. So its possible that she left via one of the entrances with the broken cameras and went somewhere, maybe made it home, and was met with foul play and then maybe someone drove her car back to the garage to make it look like she never left.
Just one theory I have. Once she got out of the view of the cameras on the video that we have seen already, there is nothing else to go on. She could have been harmed by 'friend' or foe and shoved in a trunk or backseat for all we know....
I think police believe that she never made it to her car at all.