Interesting find! Padme never returns to Naboo alive in in Episode III, so what could this scene be? Was Padme’s death originally going to be a hoax to help protect Luke and Leia? Maybe someone should ask Natalie Portman about it.
The original ending of ROTS was shot on location during production of Episode II. It was replaced by a green screen shoot during Episode III proper.
http://starwarz.com/tbone/special-deliveries/#more-1798
GL: “the original ending looks too real compared to the rest of the movie. Let’s reshoot it and make the background a fucking cartoon.”
You’d think he would have shot the baby Luke handoff both ways (Owen and Beru) just to be on the safe side. Hopefully, we get to see this footage someday.