Starring: DJ Qualls, Alexa Davalos, Luke Kleintank, Rupert Evans
Revealing mistake: Childen is getting beaten up in his hotel room by a thug, and if you watch the very last punch thrown before the scene changes, you can see that the actor really pulls his punch hard. It doesn't even come close to hitting Childen. (00:40:14)
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.