Any amount of speculation that leads to DR being pointed at as the culprit needs to understand that he couldn't possibly have known that it would take police 2 hours to finally make contact with him (which he initiated).
Think about it for a second. Police were on the scene pretty quickly. In the limited amount of time he would have had to have securely placed Jacob somewhere where the police wouldn't be looking, and than, he would have to assume that they wouldn't be thorough in their initial investigation. It's a very far stretch as a perpetrator to assume police wouldn't be knocking on your door almost immediately after the abduction.
Also consider that DR would have had no clue how fast police would have arrived on the scene. They arrived 6 minutes after the 911 call was placed. And the smoking gun is that Jacob was placed into a vehicle, and not escorted back up to the Rassier property.
My opinion is that the car that sped around the Rassier property earlier in the day was the same car that took Jacob. I think the perp was out patrolling in the afternoon and spotted Jacob, Aaron and Trevor playing and cased out the area, or began stalking. The perp could have easily been positioned with his lights off parked somewhere, and possibly could have been watching the kids through the windows. The opportunity arose when they decided to go rent videos. This area was very rural in 1989, and one could have easily parked a car in many of the field roads without being spotted. Once the kids left he could maneuver the car over to DR's driveway and wait on the victims.