Wait, wait, wait, hold up!!!

During the scene where Allan and Jessie make their way down the train Allan climbs under the car carrying the Germans surrounded by the sandbags. He then comes up from the other side of that car then bursts his way into the next car surprising the group of Germans. Not only do none of the Germans on the sandbag car even react Allan suddenly popping up behind them but Jessie would have been right behind Allan before he would have burst through the door and she is nowhere to be seen. Plus the Germans on the sandbag car would have had to notice the hot blonde climbing on top of the next car and question why she would be doing that.

That whole scene makes no sense.