The Germans have a ton of tools to work with in this scenario, even a 150, but it just isnt enough to crack the Russian defenses in the town. The Germans are slow moving, relying on wagons in this one, so it becomes difficult to focus their weaponry on a single point without being blown apart by the large amount of mortars the Russians have. The Russian train arrived on turn 3, and was able to intercept the German advance, slowing and unravelling it before they could get their AT guns in place to receive it. The German attack really just dissolved once it emerged from the treeline on board 3, not much else to say. It was the Russians day.