Anyway...along your thoughts:
I remember reading something about Deepak being somewhat of a "hot head" while his brother, Satish, is more mild. Also, something about Deepak being involved in some past, somewhat aggressive, sexual activities. So, perhaps although Natalee was "with Joran" in a sense, Deepak was interested in getting some action. Natalee sensed (or knew) that and perhaps she jumped out of the car to escape. Maybe they were at that place just short of the motel...you know, where they searched the little pond? Perhaps they chased her with the car as she was heading to the Marriot. At some point they got out and tried to force her back into the car...and that is what the supposed witnesses supposedly saw???? Otherwise, if they let her out willingly at the motel, they would not be trying to force her back in. Right?
The other brother, Satish, had gone home, but after this is when Joran emailed him saying he had someting to tell him. Joran might be very afraid of Deepak, and it is Deepak who was the aggressor.
I would think, if any of this is possible, either Joran or Satish would have cracked by now.
This would probably eliminate all the other suspicions about drugs, cartels, sex trafficking, larger involvement with criminals, etc. It would also negate that post by that sister of the FBI guy who is down there who wrote that there "...is more to this than it appears...cannot say more...." Remember that post? It is way back someplace. Unless, of course, after the struggle with Natalee, Deepak and Joran delivered her to someone else. For what reason would that be, however? Maybe Deepak owed someone something, Natalee was a payment, and Deepak forced Joran into some situation?
It is all mind-boggeling.
Just short of the hotel would put them closer to the BIG pond.
Perhaps they chased her with the car as she was heading to the Marriot.
If they did that, I think there would be tons of witnesses.