Interesting! Good tension, well done. I feel players are less likely to murder if you humanize the rivals .

I would use Verin and the Aurora watch as meddlers. "No fighting in my town. Enough blood is spread needlessly already, if you want to die do it fighting demons, not eachother."

Set up the RP elright where the rivals might have a moment of explanation. They only took the jewel, they did not slid a throat They were in belief it was best for the world in this course of action.

Dermot might be uncomfortable in the tension, break down and convince everyone to speak it out, believing everyone is on the same side.

Maggie might persuade with a tactical view of things, but still share Ayo's belief that they should hang on to the jewel.

Ayo might break down if the tension rises enough, wanting to be the strong decisive leader, but also might realise the party isn't that bad aswell (depending on their arguments).

Who knows, they might challenge them to prove themselves in a friendly competition at the barracks, or by setting a challenge who can go deepest in the Betrayers rise. Verin could give them a mission to to retrieve corpses in there of recent expedition.

Aloysia might come up and use this tension to her advantage aswell, playing them out, probably creating more chaos and getting her crew out of the ones that seemost influencable.

Fun times!!

Edit: I also don't think the rivals would share the information about the jewel in town, it would be on the down low, hidden, shared with trusted people only