I brought the party to speak with the Elven Priestess at the capitol, bringing Zephyra as usual on a playthrough. But this time, Zephyra did not offer to speak during the encounter as she always had before, even if she was offered to die in Anastasia's place. I didn't see any related errors in the console. The only way to save Anastasia's life were to sacrifice a character or Will Smith her before she blasphemed.