Somehow I doubt that someone faked hellfire. What I think is Mab is a big player in the WG's over all plan. I think Uriel is the liaison officer between her and Him, I think Harry's future was mapped out for him from the moment he was conceived.. Adjustments made along the way of course to accommodate his right of free will to make good and bad choices, but the general currents of his life have been pushing him to where he is at, and what he is a weapon in the coming war. I am willing to bet the same has been true for Molly. Born of two devote parents, one a Holy Knight plus magical talent make her perfect for the role she is about to take... Though it might not be quite so clear what was mapped out for her like Harry, Mab made sure this pawn was made ready to enter the game when needed.