I'm sure Luke knew the name of his mother just like he knew the name of his father. It would be silly to not tell him/lie to him about those simple facts. It's also very probable Luke was told his father died in the Clone Wars ("he died about the same time as your father") and that his mother died in chidbirth. Anakin's fate would be as true as Obi-Wan's version of events, and there would be absolutely no reason for Owen and Beru to fabricate a story about the fate of his mother. Therefore I am confident Luke knew both his parents names and had a general idea of their fates. This would all be beside the point however if someone is able to take normal James Earl Jones audio and transform it into the Vader voice. Like I said before that would open up all kinds of possibilities for the saga, not just this change. I'm sure JEJ has said "your" and "mother" somewhere in his career. I would prefer "your mother," but I think Padme will do.

Oh and MTH, Star Wars Part II sounds like an interesting project; I'm up for any creative reimagings of Star Wars. That said, let's put that on hold until we get the "Bleu Cheese Saga" completed.