That trailer sucks.
First off, yes, at least some of those people should be faking accents or actual German actors. If you're not Sean Connery, you can't just talk however you want.
Secondly the trailer was way too long and specific. I don't need 45 fadeouts showing me exactly who gets busted and when in the end. Also it seems like everyone is sort of jovial about the risk they are undertaking, I'd rather see a Life Is Beautiful style sort of depressed acceptance.