This is all historically incorrect. The Kaiser died in Holland in 1941, andI doubt he had a bunker even in WW I as Berlin was never bombed and there was no need for one.

But I suppose the statement could have been symbolic. But it's got the wrong war.

Wilhelm had a withered left arm, and I don't know if he could hold a shotgun, although he could shoot a pistol. The gun doesn't look to be imperial quality, however.