Compared to that group of good-for-nothings who were only capable of empty talk, Umbridge undoubtedly knew much better how to butter up her superiors. If she could help Fudge successfully expel Harry Potter just as he wished, she believed she would earn Fudge's trust and be entrusted with a major responsibility.
As for everything else, those were just minor issues.
To mobilize the Dementors of Azkaban, she first needed to obtain an transfer order approved by Fudge, which was hardly a difficult task.
Chapter 918