Interesting idea; I guess we could remove the dagger as (necessarily) the murder weapon of her parents. It would add focus on communicating that the dagger is whispering to her to be used to find the Wayfinder, but it would no longer set up the reveal about her parents tucking her away and being killed. But it’s probably worth it.
I don’t think you necessarily have to not make the dagger the weapon that killed her parents, we would just be making it unimportant that Ochi killed her parents with the dagger, which it wasn’t to begin with. The connection between Ochi and her parents is already set up by her recognizing Ochi’s ship from the day her parents left. Her hearing her mother’s screams from the blade doesn’t really contribute a lot to that revelation.
Not making the dagger the murder weapon, or Ochi the murderer, opens up a can of worms that could have drastic changes to the story. On the other hand, I’m all for drastic changes when it comes to this movie…