I think we can shave off another week from the result.

We couldn't manage a week – it takes too long to sail to the dwarven outpost (you arrive right in the middle of the action), but we did manage to reduce it by three days (the final game time was 44 days). Instead of killing the humans with the main hero, I took their capital, defeated Vitka, and went straight to the orcs and dwarves (Leto was enough for this, with two dozen archers). The remaining humans were dealt with by the second hero who arrived (Sanitar) and an orcish female hired in the castle.