I don't know if they're going for his Sword, or it's something about Barki, but whatever it is, it demands they get Barki in their power, not just kill him (Which would be much easier than this.) And all of this is just bait and switch to get him to leave Iceland--where presumably his Foe can't act directly.
Getting a Lesser Outlawing and then staying the course in Iceland, then, is the Best Outcome of the prologue, since it puts our Foe on a timer, and there's only so much money they can throw down here before someone notices and starts to counter-play. It'll make them sloppy and have to overextend to try and kill us, since they won't get a second chance at this apparent Guaranteed Shot.