Shit. I love the Grand Councilwoman and Caldwell's performance in the movie. Her voice really made the character.
I agree, Zoe brought a phenomenal performance as the Grand Councilwoman from the
Lilo & Stitch franchise and the Deep Space level in
Birth By Sleep as she brought someone who is both stern, authoritative and compassionate to the characters she interacted with (Lilo, Stitch, Cobra Bubbles, Jumba, Pleakley, Gantu, Aqua). Now that David Ogden Stiers (Dr. Jumba) and recently Zoe Caldwell (Grand Councilwoman) are no longer with us it's going to be hard to imagine anyone taking over the roles as these characters if we get a official
Lilo & Stitch world for a future KH game. Even if they bring in another actor and actress to voice Jumba (e.g. Corey Burton, or whomever) and especially the Grand Councilwoman if we see them again, it just wouldn't be the same without David and Zoe.
Gantu's Japanese actor is going to be interesting, cause while Kevin Michael Richardson (Gantu's actor in the English version) is still alive, his Japanese Voice Actor Unsho Ishizuka had passed away in 2018, so if Gantu does return and plays an important role in a potential Lilo & Stitch world for a future KH game then I'd expect they might get a new voice actor for him, otherwise they might write him out or have him say no lines out of respect for Unsho Ishizuka, much like how they kept Phil silent in the Olympus level for
Kingdom Hearts III due to the death of Ichiro Nagai.