I don't know if you understand how dire the situation was for Germany in the RCW-verse, but they were on the verge of collapsing by the time of Berlin, they literally needed any man, woman or child who could hold a gun to fight, this included the Kaiser, (as I mentioned before, they tried to get his father to leave, but he refused, and subsequently so did Wilhelm III, do you expect the Army to force the Kaiser to do something he doesn't want to do?, and don't even mention a coup, the Army had no time for such silly thoughts with five armies pushing them back they needed to fight), if France and Austria hadn't wasted resources attempting to Siege Berlin instead of outright attacking, and on other fronts, Germany would have certainly lost the War. and then subject to a extermination of horrific proportions by the French, it was a War of National Survival, and Germany was going to either win or be eliminated from the face of the Earth, and every German had to stand and fight the Fascist invaders, even to the point that the Kaiser himself had to fight.
Indeed, the early years of the War were quick and unexpected defeats for the Imperial German Army, who were quickly steamrolled all the way across Germany to Brandenburg and Prussia proper. (pre-Napoleonic Prussia).