On Eva's Hammer, the stars and stripes is seen in various places, sporting fifty stars. The 49th and 50th states are Alaska and Hawaii respectively, inducted in 1959, in this timeline it's likely these were never inducted and the flag should have only forty-eight stars.
One of the notes that can be found on the "Ausmerzer" depicts an Oberleutnant Decker as the second in command on the ship. Even considering the nature of the game, it is highly unlikely that an Oberleutnant (a First Lieutenant) would be in this position on that huge ship.