S2·E3 To Be or Nazi Be

Supposedly, an old man who knows the secret of the legacy of Hitler is living on the other side of the Berlin Wall. Walls are no problem, and taking Genhardt, the old man, to the West is easy enough, but he is absolutely senile and recalls nothing about any legacy. Therefore, the plan is to reenact a scene from the period, but... What has happened to the legacy, anyway?