She wouldn't be able to run until she was positive that Aberforth was truly successful in his escape. Getting him out of the Ministry was only the first step. There had been no news of him since he stunned her disguised as Umbridge. Only one person could tell her what she needed to know without blowing her cover. She wasn't positive that he would be willing to help her, but he was her only hope. The worst he could do was tell her "no'... or turn her over to the Resistance for punishment.