I will say that the dagger thing is a really good idea for an edit in which Rey is truly a nobody. The only reason I wouldn’t use such a thing on the other thread is because it’s unnecessary when the whole purpose of that concept is that Palpatine may have had a part in manipulating the very nature/destiny of everybody. But this allows you to do the same thing without getting into influencing the creation of life. Granted, that is something that had already been established as something Palpatine was interested in, and not so much fashioning Sith artifacts which possess you Darth Momin style, but it still works.

So take the example of the scene between Finn and Rey on the Falcon. Both of our explanations satisfy why she’s hearing whispers telling her to go destroy Palpatine in her anger. In your case, it’s because this is after she’s retrieved the dagger and it’s influencing her actions. In my case, it’s because she’s just been told her true origin by Kylo and it “unlocked” the nature/purpose that Palpatine planted in her since birth.

EDIT: Ya’ll ever read The Silver Chair by C.S. Lewis? That’s what this other idea reminds me of. Personally I love the idea that Kylo was a good man under a spell by Palpatine. And if he didn’t return to Vader’s mask every so often he’d start to slip back to his normal personality (like how the prince has to sit on the silver chair every night). But others probably prefer character agency, and I can see that argument as well, which is why the other thread’s idea can exist because it places a greater deal of emphasis on that.