I always imagined right before Madine dies the shot becomes green, if you know what I mean (rhyme by the way). Like as he's saying something a green filter fades in to represent the DSII laser fire, then the ship explodes.
As for the Vader vs. Jerjerrod scene, if we can dub it that's perfect, but otherwise I think it could work without a line from Vader at all (Jerjerrod says Vader can't see the Emperor, Vader chokes Jerjerrod, Jerjerrod changes his mind).