Because those "key facts" don't support his agenda -- which is to find Rove and/or Libby guilty of something!
It strikes me that there is another piece of evidence that this whole affair has been manufactured, then inflated beyond reason.
The universal MSM premise is that the Bush administration was actively seeking to destroy Wilson (e.g., "...an intensive period in which senior White House officials were scrambling to discredit Plame's husband, former Ambassador Joe Wilson..."). Every news story contains a statement like this as "necessary background".
However, thanks to Cooper's testimony, we then hear the actual reports of this alleged attempt "to destroy Wilson". And what does it amount to?
Cooper calls Rove.
Cooper asks about welfare reform.
Cooper broaches the Wilson column and asks for a response.
Rove responds off-handedly, "I hear his wife, who works at the agency, sent him. I wouldn't get too far out there."
That's it. Whatever it is, it ain't an intense media campaign to discredit Joe Wilson.
In other words, just about everything the MSM has reported about this affair has been bent into an unrecognizable form by their pet bias.