Brey, they don't come back. They simply do not come back. Nazis do not later on decide that they were wrong about all that Nazi shit. What they do is go very quiet around about the time people start unaliving nazis because "hello? It's fascism and they're fucking FASCISTS" and burn with seething resentment for the rest of their lives, plotting a return of their mythic past and Nazi bullshit - always, every time.
You can't even get rid of them, you can simply make them afraid. That's the SCORE.