The only problem with that is the fact that the witness(es) last night also saw a "silver ladder" on top of the van. White vans are common, but waiting for a van with a ladder or ladder rack would seem ludicrous.
OTOH, although that was part of last night's description, it was omitted from Chief Manger's description this morning.
This gives you an idea of how difficult it must be to synthesize eyewitness accounts: how much is factual, and how much is influenced by reporting on previous events (in this case, Friday's reports of the van with a "ladder" or "ladder rack").
This could also be a tandem operation -- one drives a white van to provide cover, the other drives a car. One or both might even have been stopped, didn't seem suspicious, and went on their way. Sounds incredibly diabolical, but isn't that what LE is dealing with?