Invincibile Carloman

I am fighting against Carloman in the DLC Cross of Vidar, chapter 3. He has ammassed over 80 Military units around himself. I don't think it was meant for him to have this much military units, growing insanely after every attack, instead of decreasing. My hero from boar Clan was killed before I could react after some keyboard troubles and now I'm at loss.
Even when my character and Rig do try to surround him, attacking one after the other, managing to overtake most of the place around, so that Carloman should have been cut off from reinforcements, but no. I am at a measely 30 units of military and every attack is so fast, my units get decimated in seconds.
So I have to wait until new villagers are available to make new military reinforcements. Please fix this Q_Q