It’s not her fault.

The Nazis, upon whom the empire borrows much, have an interesting management style. The theory was that leaders set goals and allowed subordinates a free hand in achieving these goals. Some of you may find that attractive, but there is a fatal catch. The subordinate is only “Free to Obey”, to achieve goals, never to set them. Even worse, responsibility is delegated with the tasks, so failure is the subordinates’ fault. It’s never a bad objective, scarce resources, or bad information; the people making the decisions are shielded from responsibility.

Now back to Dedra. In her exit interview with Krennic, she explained how the ridged order and information control caused her to digg into places where she was not allowed, just to get the information she needed to pursue Axis. Nobody would have faulted her for arresting Luthin if he had survived.

Had all of her misdeeds come to light under the auspices of success, she would have been praised for her cunning. She was constantly stymied and blocked by different organs of the Empire, set to cross purposes by pride, ambition, or stupidity. Decisions made by the likes of the Emporer or Director Krennic are what made Luthen’s long anonymity possible.

Dedra didn’t doom the Death Star, she was on the verge of saving it. And she was fighting the Empire as much as the Rebellion.