Okay, I know this come with the world's largest "ackchyually..." stapled onto it, but isn't it clearly in the rules for cops and robbers that touching a fellow robber in the jail frees them? Maid did that before getting caught and the lil' sis is already free at that point, without getting caught at the end whistle. They won.
...Though this steps past that whole wrestling side act here, as the cops don't really have to physically drag the robbers to the jail, just catching them is enough.