I played it frame by frame, and it isn't a CGI effect. The man was right against the lift, so if she had been there physically, he wouldn't have
been able to stand so close. Also, prior to them entering the lift, you see a light anomaly in the lift prior to them entering.
If you play it frame by frame, you will see that she moves from one wall into another in the lift. Obviously, where the lift is now, there must have
been a floor of another building where obviously this business now stands.
It is an amazing clip, but I could not see any signs of tampering. I think it is authentic.


It's a pretty long one, but the end of the video worth it. 

