After losing many other men, for what does Novinha tell Ender she will hold him personally responsible and how can Ender avoid this responsibility?

After losing many other men, Novinha tells Ender she will hold him personally responsible if Quim embarks on a mission to stop the rogue pequenino fathertree, Warmaker, from spreading descolada thoughout the galaxy. To avoid this, Ender must use his influence to prevent Quim from embarking on the mission.