A very easy way to leave when the nazi turned out to be a demon/vampire.
in 1940-41, once they have trapped him (in the farm as explained by the father), they buy cardboard boxes, paint the runes on them, wear them and leave the farm.
This way, the nazi demon, who can't come out the farm, remember ?, does not have food anymore and starve to death.
Big plothole, isn't it ? ;)
SPOILERS
You know what I can't figure out? So Victor had been tied up and cut right. By who? I have to assume by Leise because of the bell thing Leise rang towards the end, right? So, if she cut Evan open and poisoned the guy with the bone dust of the vampire nazi dudes ancestors, then why didn't they do that in 1940 when this *beep* started going down?
It doesn't make sense. Like chewbucca. He's a wookie from the planet Kashyyyk, but LIVES on the planet Endor. IT DOES NOT MAKE SENSE.