The problem is still Frank. Lucas hasn't said one thing about Darabont's script in public...not one. He's kept his mouth shut and decided to go into a different direction....with Spielberg's approval (no matter Spielberg's true feelings on the situation). Frank has been going on and on about his script for years now. It's time for him to get over it. What's the point of harping on it again, even if he was just asked a question....?
Frank just needs to let it ago. All he had to do when asked by Lucas if he wanted to write the script or not was to decline it. This is what happens when you're a writer for hire. Sometimes it works out, sometimes it doesn't. End of story, really.