Last minute. The man who wrote the damn story said Vader was the hero of the story
"Now, there's a hint in the movie that there was a Sith lord who had the power to create life. But it's left unsaid: Is Anakin a product of a super-Sith who influenced the midichlorians to create him, or is he simply created by the midichlorians to bring forth a prophecy, or was he created by the Force through the midichlorians? It's left up to the audience to decide. How he was born ultimately has no relationship to how he dies, because in the end, the prophecy is true: Balance comes back to the Force"
Luke was on the Death Star and managed to get out and had time to sit and chill and talk with the nikka before he dipped. I'm sure they'd have murked that nikka and go away