I think “his visions discovered Rey” is probably vague enough to work (while still being short enough), since it could apply to both Ochi or the Emperor based on Finn’s previous sentence. Perhaps bringing the dagger into the discussion just makes things too convoluted - if it were Ochi that had the visions, it would be the dagger that gave them to him anyways.

For some reason, simply changing it to “visions” also makes the sentence feel a little less location-oriented to me, at least. Probably because the dagger serves as a whisper compass earlier in the film.

We have to remember that the purpose of this scene in the original film was to transition to the “twist” that despite all of Palpatine’s previous actions in the film, he apparently wanted Rey alive. In Ascendant, the scene serves no purpose except to muddy the idea that Ochi needed to kill Rey on sight. In this edit, it’s meant to explain the last bit of Rey’s backstory, which is how the Emperor even knows about Rey in the first place seeing as how her parents died in part to keep her a secret. I think this new line ties in better with Kylo’s line of “He saw what you would become” better.