Yep, your idea does make more sense. 

Crescent~

We've been sitting in the cold cell for a few hours, although l'm not sure. It's hard to tell the time with no windows. Tigereye is awake and she thinks her shoulder is broken. Unfortunately, we can't do anything about it.

Footsteps echo in the empty corridors as someone walks along them. There is a jangle of keys and the guard opens the door. 

"The Duchess wants the elf," he says, glancing at me. "Obey without struggle and no one gets hurt."  l then notice that he is holding a Steam-Crack.  l get up and quitely follow the guard out the door.

l saw what the Steam-Crack did to Tigereye. l don't want that happening to me. l glance back at the others as l leave. Jackson gives me a look that says, Why you, of people? l shake my head to indicate that l don't know.

A few minutes later, through many hallways, the guard and l are at the door of the Duchess's parlor. He opens the door, pushes me in, and leaves.

The room is cold and dark, with many chairs lining the walls. The Duchess is sitting in one of them, wearing a different dress now, a dark green one.  

"What do you want?" l say in an icy tone. "We did nothing. We only want to help."

"Help? With what? l have everything under control."

"You don't!" l almost yell. "The Thrum is broken, the city in chaos. Is that what you call control?"

"Now, now dear sister," she says, lightly. "Who needs the Thrum? This pitiful city is-"

"Sister?" l go pale with shock. The Duchess is my sister? "B-but how can that be?"

"Simple. l was the first-born child, the heir to the city. You, on the other hand, have no right to inheritance and were worthless in the eyes of our mother. You were abandoned." 

"How could've she?!" l exclaim, frustrated. How could've my mother just abandoned me? 

"Back to the subject," she says, coldly.  "Little sister, you must join me in my glorious plans for this city." She leans forward, gripping the arms of her chair. "We will make the city better than it ever was." 

"By cutting off the main sorce of energy for the city?" l say, sarcasticly.

"You don't get it. By destroying the Thrum, l shall make the whole city dependent on my mercy. l have already locked the gates so no one can get in or out. l will give everyone a task, and they will have no choice but to do it, or die."

l raise my eyebrows, trying not to look frightened. "Task? What sort of task would that be?"

The  Duchess smiles a fake smile at me. "That would be the task of building my great steam war machines."