/lit/ - Literature

I'm stuck with one of my plots. For /write/ regulars it's me the humans and monsters guy.

>monsters go on big campaign to kill the humans
>monsters split forces in two. main character leads one force, secondary character leads the second
>second force is defending the back of the first force while it sieges the human capital
>second force gets btfo and the second force commander starts torching the countryside with the idea of delaying the human flanking force long enough to give the main character and the first force a shot at the human capital
>main character has to decide between abandoning the siege and moving to engage the human flanking force, thus losing his shot at the capital (and abandoning his quest for revenge against its feudal Lord), or letting his monsters torch the countryside and butcher the peasants (which he doesn't want to do)
That's where I've plotted it out to. I don't know what decision he should make.

For reference, here are the characters available and their goals:
>main character
Get revenge on feudal big bad but minimise collateral damage because he's not all bad.
>secondary force leader
A bit of a runt and enjoying the first bit of real power he's ever had, enraged that he was defeated, hates humans, viciously trying to claw back his self-concept as a successful military commander and warrior. His subplot needs to be concluded by the outcome of the main character's decision.
>main character's sidekick and sidekick's brother
Sidekick recently got turned into a demon and is coping with the side-effects. His brother is concerned for him. They just concluded a subplot and kinda have nothing to do at the moment so I'm keen to find a use for them.

This is coming towards the end of Act 3 so I need a climax. I feel like this choice makes a good climax but I can't see how to use it to resolve the main character's story.

Pic related is the map. The secondary force was at Ferlangen, and the main force is at Dassel threatening Wolfenburg. Human forces are occupying Ferlangen preparing to march South to Dassel, and defending Wolfenburg licking their wounds.