I'm a bit uncomfortable about this question. Even before Francis gave the OK sign to the various bishop's conferences about allowing people in the state of mortal sin to receive the sacraments after publishing Amoris Laeticia, all cardinals and the pope already adhere to the errors of V2, which do contain heresy and blasphemy.
Is it possible that all the cardinals and the pope could publicly defect from the Faith? And if they could, how is it that they would continue to hold office in the Catholic Church? Can any non-member of the Church be pope or cardinal? Could the Dali Lama, an atheist or a Mohameddan be elected a true pope? Where does the line get drawn?