Its certainly possible that both low beams are out.  Do you start the van with the headlights on?  Sometimes there is a voltage surge as the voltage regulator "wakes up", that can blow the bulbs.  I have not heard of this sort of problem with Bosch regulators, but it could happen.  When this happened to my Dad's Ford (blowing both low beams, at night, a long way from home) the mechanic at the gas station said that he has seen the problem several times before.  He didn't have any bulbs in stock, so he adjusted the hi beams down a bit!

Bill