At first when Sabo and the revolutionary army were introduced, It was surprising that their bounties were so low for an organization that’s trying to overthrow the World Government. It is possible that the revolutionaries have connections in the holy knights, and move through the shadows.
Her design is similar to the revolutionary design (accessories like the googles over the hat). We already know that Dragon will start war with the World Government soon. The best way how to learn about the organization is through a spy since the World Government is pretty secretive to the world.

Market:

Resolves YES if Gunko is confirmed to be a spy for the revolutionary army/Dragon

Resolves NO if Gunko is not confirmed to be a spy for the revolutionary army/Dragon