Tagron,
I'm sure there will be a lot of soul searching on all sides once the investigation is concluded. By now we seem to know reasonably well what happened, but as Ptkey put it some posts earlier, when it comes to the why, the swiss cheese seems to have gone rotten to the point of hardly having any cheese left...
There appears to be a massive (and possibly deliberate) confusion as to what rules exactly applied to the flight, what authority did ground control have to issue binding instuctions to the pilot, all shaded with the very evident pressure on both the crew and the ground controllers to complete this flight. When it comes to establishing direct cause, the question of why did the aircraft get 60m below the glideslope pales in comparison to why was this approach commenced in the first place.