so does anyone know how to unlock the Kashyyyk Prologue to replay with the Apprentice? or was playing him on Kashyyyk something only the devs can do? lol

I don't think that's possible. It's a level designed only for Vader.

Well, I'm on my second playthrough now, and what I did was I simply started a new game, saved it in a new slot and played only the prologue, and then I switched over to my other file and started with the TIE Fighter factory mission with all of my powers an unlockables intact.

So basically: Play the prologue as a new game in a different slot, and then switch over to your other save slot afterwords.