Love the lower/higher dice mechanic — been thinking about maybe using one recently and this is a great, condensed example of how it's best put to use and colored with some setting flavor. Trying to think of some kind of house rule to link players' actions to each other, since they're on a chain gang and all. That was the notion that drew me to check it out, but the rest made me stay to comment :)
That flavor is also excellent. Love all of the complications on the GM side. I definitely want to see more content in this setting!