I mean, three likely answers, in descending order of plausibility:
1. Xihirli has an inherent defensive attribute that she didn't share, either gained through becoming a wolf or just inherent to her;
2. Cultist Confiscated your power (not sure if Caedorus would have stopped this?)
3. Xihirli has a broken scry and doesn't realize it, and you were the one to kill Cultist.