I think the audio change for Vader should only be applied for the Erso section (and thinking about it, there might be a way of removing the reference to Galen without using other Vader audio sources). The pun isn’t great but is what it is (as a Prequel film, it doesn’t really destract with the “No!!!” of his previous appearance).

Original: “I expect you not to rest until you can assure the Emperor that Galen Erso has not compromised this weapon in any way.”

Edit version: “I expect you not to rest until you can assure the Emperor this weapon has not been compromised in any way.”

Don’t know if that would be possible though.