The ending to ROTJ:R will be the 1983 version of the film. No planet montage, no Hayden and no Victory Celebration.
And there won’t be 2 audio tracks for ROTJ. I really dislike the Victor Celebration music, even more when realising its just copy of a piece of music that was used as a rough guide from a Native American mini-series. I’ve always felt since 1997 that it sounds so out of place in the film, and now i know why
About the ending celebration, have you considered using a piece of music for that scene that isn’t Yub Nub or Victory Celebration? I understand why you feel that Victory Celebration is out of place with the usual style of John Williams’ score, but Yub Nub is even more out of place in my opinion: Way too cheesy and kiddie-feeling for what’s supposed to be a heartfelt ending.
My personal suggestion would be using a non-diegetic piece of orchestral music, preferably something written by John Williams. The shots of the Ewoks playing instruments would be cut out, and some extra shots from the SE ending could be added to make up for those cuts. Someone on this site already did a test of syncing the celebration up to the “Luke and Leia” theme, and it worked pretty well.
Just a suggestion though: not trying to tell you how to make your edit. If you like Yub Nub, that’s fine.