idk some of you are confused. It's the backstory from the first timeline before the current one. Remember Shuli herself doesn't know how and why she actually died
this is what actually happened, to Shuli, the kids, Nora, the knight and the Cardinal.
the cardinal arranged her death, which the knight blamed himself and went mad/insane for Shuli's death for failing to protect her. The capital guards and the emperor's own guards can't find any evidence of foulplay too.
The one who visited the knight in jail was Jeremy, prob because he wanted to know what actually happened to Shuli since he's the only one who know.