On the subject of distances between Israelites and Germanic Witchcraft I'd like to remind people of the merchants that traveled the world, crossing great distances, and reaching places we now call north america, russia, egypt, etc. etc. etc. and practiced trade all along those places.
Trading happened in those times. Longer distance trading than most of us realize.
The world is smaller today, yes, but it is not impossible that "witchcraft" would have made it to Israel, though in all probability, there was probably another, similar though not the same, practice already established within that region.