beta
Hear me out.
It's obvious that he knows who she is. And he probably regresses with her every time. You know how he said in the memory Leah saw that "The bridge broke everytime". Of course he knows who she is and that everytime she die, times goes back.
Now, who is killing her and for what?
Of course the killer knows she isn't really dead, his wish wasn't granted, so he knows Leah is alive.
My question would be, what is his wish and why does he have to kill her. Is it because of her power?
I think that's one of the reasons the father told her never to leave the palace. I think he knew she was destined to be killed because of her power. Maybe her power isn't just memory reading.