DW3XL: Bodyguards go against our troops GLITCH

I was just trying to level up my bodyguards in The Nanman Campaign, when all of a sudden my bodyguards began defeating our soldiers, as in, they went against us. I guess it's a glitch because they were chasing around a Private soldier within the gate of the opposing team and once I shot him with my arrow, my bodyguards began acting different. As seen from the footage, the are only able to give damage if they aren't directly within the frame. If I look at them, they don't do any damage. In the end, they defeated our Gate Captain and well unfortunately, Meng Huo won't be able to receive anymore troops.
But once encountering with the enemy, the bodyguards go back to themselves and attack the correct enemy.