That's ridiculous. Actively participating in the slaughter of hundreds of thousands of innocent people is not some youthful indiscretion. This man had a front row seat to exactly what Nazism became. He can't be excused or rehabilitated by the fact that he signed on before that happened, because he stayed on even after things took an unimaginably evil turn.
And just because someone doesn't mug and sneer like a movie villain doesn't mean they aren't evil. The true evil is whatever allowed these monsters to exterminate millions of human beings, then go on to lead lives of their own as if nothing had happened. The fact that nazis can seem "normal" decades later, in spite of what they did, is more horrifying than if they behaved like cartoon villains proud of what they had done.
Assuming he wanted out, how would he have gone about doing that?