I didn’t know there were other people in the Vader suit other than the three OT guys.
Lots of the lightsaber fight scenes were done by other actors. Apparently Prowse was bad at it and broke too many props.
No actors were used in fight scenes other than Prowse. I thought Bob Anderson (stunt guy, not an actor) did the fight scenes and he was the third guy in my list. Feel free to throw names if you know this guy…