I can also confirm that the old battery can be carefully removed without disconnecting the final ribbon cable, but that cable was also glued down and needed to be freed a bit before the battery could slip out.

I also had a relatively brief moment of fear when I tested it with the replacement battery still partially unassembled, when I could hear some quiet(ish) RFI noise. After carefully pushing the cables back to their original place and fully reassembling the questionable earbud, the RFI sounds were fortunately no longer present. I hope they don't come back later!