I think I can translate Bimmy into Janet-ese.
If you start the beginning of the story with C in her hold and being notified of the news of her brother, then you have 'placed' her in context. The character probably runs to her horse and starts to ride right after the news. Lotsa drama in this moment.
Potential beginning chapter: what does the hold look like? Is C doing the books and wondering how she is going to pay her brother's latest debt? She gets the horse saddled without the staff realizing (this is night and you mention raiders...she wouldn't normally go out alone onto the moor, would she?) and orders the gate guard to open whatever opening there is in the wall...she rides out... Does a servant see and try to stop her? What kind of guards does she avoid? She rides out into the dark to save her brother from making the biggest mistake of his life and ruining them both.
Cut to M. He rides with his men, responding to the warning of an upcoming attack. He would be assessing the men and how they've responded in the past to a fight (again, mention the raiders because this is his main experience with combat). He would think they wouldn't have bows, perhaps, making him more willing to ride into dangerous areas than he would otherwise. He would be thinking of the layout of the endangered hamlet, as well as the amount of people/ children there. He would be scanning the sky for signs of fire lighting the underside of the clouds. He would be pacing the horses so they wouldn't tire when his men approached the town. He would be scanning the ground for tripwires on the road...this would a certain way to bring down his men in an easy pile. Then he hears the scream as C is shot. On alert, he rides closer.
Does this help?
Don't worry about K and his spreadsheets. Just keep writing. The spreadsheets are awesome to look at. When he pulls them out, it's usually to make a point. Wait till you see his drawings. They're even better.
A