I did this last night, first go, I’m about Level 11, strength 13. I poisoned two pots in the Cuman bit of the camp, I did not burn the arrows or go into the upper stockade during the recon. I did not set fire to the pile of hay either.
We attacked across the narrow bridge, I could not get a bead on any enemies with my bow so just jabbed and slashed around the edge. when they told me to deal with the archers I tried to shoot them but I think I only hit one once, in the arm, but they came down the hill or ran away after a bit. Defending the battering ram was close as I was fighting 3 enemies at a time, and I was down to half health by the time we got through.
Despite having half health I defeated Runt fairly quickly with a couple of perfect blocks.
I will say it would have been useful to know that I could neither access my horse’s inventory nor drin any potion once it started, I had all the potions lined up for taking less damage etc but had to do without them in the end.