If I were in charge of US propaganda... ;-)
...I would almost certainly deny being the one responsible for his death. I would never admit to having proof of his death for fear it would start a chain of cells to be activated and cue last gasp terror attacks.
This way if he is dead - all the terror cells that now just await news of his death - will wait for a long, long time.
The US is not as lame or as clueless as we have to paint ourselves sometimes ;-)
Best wishes,
SDAI-Tech1