It's the camera crew working in the other room. You can plainly see an equipment stand in the room where they are obviously working. They use bright lights when filming and it can cast a shadow if you are walking about the room. No way is this his ghost. He said in an interview that he'd never go back * except maybe to visit. And that it was no longer a home...but a house. Why would he visit a place where he felt violated. He's finally at peace.