And like in her time, Mia realized that the Alliance couldn't do it without inside help; getting inside hadn't been easy for Voldemort. He'd utilized Draco Malfoy to get his Death Eaters in during her sixth year. And during the Final Battle Voldemort was in control of the government and the school itself when he attacked at the end, yet he still couldn't get in until he'd crumbled the wards with multiple sustained and heavy magical attacks.