I'm assuming that the novel is still attributed to George Lucas because it always has been. I don't know a lot about the publishing world, but author's names never change. Everyone knows that Mark Twain was a psuedonym, and that the real author was Samuel Clements. But you will never see Tom Sawyer or Huck Finn credited to "Samuel Clements" in any bookstore, but always "Mark Twain". It might be something like that going on. Since it was originally attributed to George Lucas, it is stuck that way.