I am experiencing the exact same problem. At first the dealership blamed the Magic Start ignition kill security system and it appeared that the problem was fixed when the system was replaced. However, about 10 days later, the car failed to start again. The Magic Start tech bypassed the system and the van still would not start. The tech was nice enough to perform some diagnostic tests to see if there was a charge running to the starter relay and there was. He thought that the problem was either the starter relay or the neutral switch. The van will be towed to the dealership tomorrow and I will let you know if the problem is resolved.
If you have discovered a solution to this problem, I would greatly appreciate your response.