The first time Dawn didn't get her peanut sauce on, it was blind judging and the judges were unaware there ever was a sauce. They commented that it probably should have a sauce, but the dish was good enough to put her in the middle.
Second time was the tofu challenge and as biakbiak noted, she was disqualified on that round.
Third, she left the red eye gravy off two dishes. Fourth the gougere was left off one dish. I don't think either of those changed the dish dramatically. Maybe the gravy, and maybe she should have been in the middle rather than bottom or top. But they always have