I think the movie was intentionally a bit "Forrest Gump"-esque, we're not meant to focus on the Nazis, the Nazi sympathizers, or the treasonous business owners. We're supposed to focus on the human bond, the relationship between the main characters, and how it all comes together at the last minute to resolve the plot (and the Plot).
I'm of a mixed opinion regarding the marketing, on the one hand the plot they uncover is a fundamental aspect of the story and would have definitely drawn more attention, but on the other hand drawing attention to the Plot in the wrong way was exactly what they wanted to avoid, do they leave the Business Plot out of the marketing or do they give in and weaken the whole message of the movie?