The premise that any deviation from "what Ron really wants" must be Disney/Lucasfilm influence is sketchy because we of course have no way of discerning what those supposed deviations are.
I obviously have no way of knowing how much of a free hand Ron has been given (though the blunt "A Game by Ron Gilbert" is certainly Lucasfilm trading on the perception that he's the creative authority here), but it's very possible given past comments that he only agreed to this in exchange for final say. And if that's the case, who's gonna satisfy this need for a villain in the event of disappointment?
What I'm driving at here is that it's highly possible that Ron with absolute creative carte blanche will be delivering something quite a bit different than what many people have already decided in their own heads is "the true vision." I think a lot of frustration can be avoided if people susceptible to that thinking can see the illogic of it. This previaling notion of Ron having a fixed, shrinkwrapped schematic for MI3 since his LucasArts days that exists outside of time and now needs only to be "let out" is a myth, and one that doesn't really acknowledge the reality of how game development works.