Last July I released (self-published) a 1st book in a trilogy. About 6 months in I had barely (and I'm being generous) any sales and a few reviews. I did a "Book Blog Tour". When I did that I got reader feedback that one of the characters has a name too close to a religious name while all the other names are fantasy names. With using a religious name it could then only market to a certain group. It was suggested I change that name. I agreed since every one else's was fantastical, it did make sense. So, I made the change and just fixed the documents on Amazon. I've had more sales and more reviews since the name change. Well, a year after the 1st book's release I'm getting close to releasing the 2nd book. Here's my dilemma.... I haven't told my editor I did that name change. During the editing phase I kept the original name because I couldn't think of how to tell him I changed a character's name after it was already released. I send him about a 8 paperbacks when my book is done and then he passes them out to his circle. So, the 1st book with the original name, he has and it's the one he's passed out. Less than say 25 people ever read the story with the original name. Am I over thinking it that my editor may find it bad that I made that change?
Your editor is normally someone you hire. You're the boss, and if you think changing the name is best (and you have good reason to), who cares what the editor thinks? Sure, they should probably know about it, but you're the one paying them and they're not going to argue if you make your reasoning clear.
You wouldn't be the first author to do a revision and republishing of a book. Christopher Stasheff completely rewrote his book King Kobold after it was released and poorly received. His wasn't just a name change, he completely eliminated a character along with other things. The 2nd version is titled King Kobold Revised to differentiate the two.
Depending on the type of editing they're doing, they may argue with you if they think it would be to the books detriment, but you're right in that they don't have final say. But why bring in an editor if you're not going to listen to them, anyway? My advice would be to discuss it with the editor and, assuming you didn't find them advertising on Craigslist, seriously consider what they have to say. Chances are if they do this for a living, they have a lot of experience. But also do what you feel is best.