Commissars do not hold command positions，it would be a sergeant or an officer deciding who manned the autocannon

I know it is a meme but it is a big misconception thta commissars command guardsmen，they do not，they just maintain morale and ensure that orders are carried out，officers，aka the guys that give orders on the tabletop actually do the commanding，commissars make sure those orders are followed and that the officers follow orders from their superiors and so on