Something I am confused about, is in one of the last scene (58:40 to 59 minute mark), Izzie dreams that she is in that elevator like in that scene in 2.27. Then she sees George in army attire. They see each other but don't say anything. Izzie has this look in her eyes meaning that she knows something is off. If she saw Denny, she would know she is dead because he is dead. But since she saw George, she was confused. That moment kind of confirmed that he actually did get hit by a bus.