Why would NH cover for this other perp and lie and say he dropped her off at her apartment complex if he really dropped her off somewhere else and she got into another car? I can see why he would lie to save himself, but why cover for someone else?
Again, the cell phone pings have to be considered and explained. In the above scenario KB is either not taking her phone or somehow her phone is disabled so that the phone no longer pings as she gets into this other car and that car takes off.
It would have to be that NH did indeed drop her off outside of her apartment complex and she maybe pretended to walk away, but instead had someone else pick her up. In this scenario NH has no knowledge of the other person. He really thought she was going home. So this requires us to believe the words of a RSO. Not too comforting I'll admit.
Do cell phones ping when turned off? I'm not sure I've ever seen a unanimous answer for that, and I'm not cell phone ping savvy.