Paddle thingies ensure the bomb is vertical at the point of impact. I assume they fold in when they detect the bomb is vertical. If I misremember incorrectly, Saddam's main bunker chamber survived because it was very strong, and also the ceiling construction was layered to fake floors. So floor-counting penetrators went off too soon. But the roof of the bunker would have been too strong anyway.
So no, the bomb probably isn't too large, especially if they haven't fixed the floor-counting issue yet.