Somehow I got the idea that Daddy VDS did get his son around 11, brought him home. The son called Deepak and/or his brother about going back out to C and C's because Natalee wanted him to go there. Joran was not supposed to be out, nor was the younger brother. But they picked him up and they went there. Then, later, (or early in the a.m.) Joran's dad was called (again) to get Joran in the parking lot of McD's. That is how I have come to understand it.
Maybe the brothers were told by Daddy VDS to take off with their car and clean it up real well, while Joran and Daddy took Natalee back home to decide what to do with her body. There was a call to the the DJ who lives in Santa Cruz at 6am in the morning...
I think that might be very close to part of the story. Which is why Daddy VDS was called. There was some problem, and even though Joran was out when he was not supposed to be, they needed Daddy VDS. I bet he was hopping mad that his son had skipped out, but if something serious had happened to Natalee, he probably immediately did what he could to cover it up.