Other mistake: John is promoted to Oberst Gruppenfeuhrer and assumes the uniform of such. He is soon after promoted to interim Reich Marshal. And then he is subsequently fully promoted to Reich Marshal. But he continues to wear the rank insignia of an Oberst Gruppenfeuhrer.
Suggested correction: John does eventually put on the insignia befitting a Reichsmarschall. It's safe to assume he didn't immediately put it on, either because it took a short time to produce new insignia and send it to him (they wouldn't stock insignia for a rank only a few people hold), or because he was still only acting Reichsmarschall.
Other mistake: It's 1962 and in this reality the Nazis and the Japanese empire won WWII, therefore the United States, Europe, Russia lost. Africa is enslaved. The Japanese detectives go to a suspect's house who turns to be a Nazi soldier who shot the Japanese emperor to instigate a war between the two nations. The Japanese detectives locate a Russian made SVD-63 aka Dragunov, 7.62x54r caliber. How could Russia be making weapons if it was occupied or annihilated? Under these dictatorships weapons are banned. (00:07:30 - 00:09:30)
