She certainly didn't foresee Pei Ye's escape.
She couldn't have imagined how he managed it; he was utterly exhausted. After two days of close care, she knew well the state of the man's body. In those circumstances, being able to employ even half a Heart Sword technique to break Zhou Jie and Qi Zhiran's deadlock was already an upper limit that swordbearers across the world would struggle to reach.
If he left the cell without taking anyone—he should have left alone, as that situation warranted little trust—Nandu would not have succeeded so easily.
Yet he chose to take her, which Nandu hadn't anticipated. As a result, she succeeded. This made her unwilling to face him for quite some time.
Setting aside all else, once that small dagger pierced the neck, he shouldn't have had any capacity for resistance.
