I think you can get to Belgium from Germany without actually passing through the Van Switzerland belt. If johnwitts has a look at this thread, he could probably shed some light on this. He contends that he actually travelled from the UK to Switzerland, a claim that is the subject of some debate - primarily because of the deficient technology he says was used (a Fiat Uno). But, if he did go, he must have passed through the Van Switzerland radiation and presumably has survived to tell the tale.
Are you there John.