My guess is that maybe George felt Nute Gunray needed to die onscreen, since he has been a baddy over all three films. But I don’t think most people would have cared. They would have rather seen Anakin kill some Jedi I think!
Yeah, so when Palpatine tells him to go to the temple and then to Mustfar, it cuts to Anakin around when he starts saying to wipe out “Nute Gunray and other seperatists leaders”. You could change that dialogue to something about a Jedi outpost, or you could just have him not mention Mustfar here, and/or keep him saying the remaining Jedi “will be dealt with”.
When Anakin speaks to Padmé, you could trim the dialogue to just say, “The Chancellor has given me a very important mission…on the Mustafar system.” Or add some dialogue about the Jedi if it can fit.
Then if one were to reshoot the Mustafar bits, you could just have one of the Jedi briefly explain why they’re there. I would just say that a group of Jedi regrouped there, and maybe they think Anakin is another survivor. And then Anakin uses the Force to close the doors.