Sure they would. They don't care, any more than the feds care if people believe, temporarily, that the CIA did it, or some renegade scientist at Ft. Dettrick, or a "beltway bandit" defense contractor. It's all functional. The FBI was never tasked with figuring out where the anthrax came from. In the first place, that would have been the job of USAMRIID and the Army's Dugway Proving Grounds Biological Warfare Unit. They are already set up to handle precisely the scenario that has unfolded -- the FBI has neither the expertise or the facilities. In fact, if you followed this story closely, you'll have read that the FBI never even spoke to the leading experts on anthrax. It's not their job, nor was there ever any doubt about where the anthrax was coming from, at the highest levels.
I remember, months ago, wondering how they could possibly keep up the stall -- it's been an education to see how easily public perceptions can be managed, largely through the art of saying nothing.
You: Sure they would.
Not the FBI. The people there are looking to protect themselves and their own positions. No one in the FBI would ever admit that they haven't gotten necessary expertise externally when they didn't have it in-house.
Now, someone else in the government might have said that. Or the reporter might have taken a report from the FBI and added his own interpretation based on extra research (interviews with the people involved).
The interesting thing now is that they have a problem on their hands. Between the FBI's numerous statements and the extensive dissemination of Rosenberg's theory, large numbers of people now believe that the anthrax attack was carried out by a lone domestic nut. The propaganda has been too convincing. How are they going to back out of it?
At this point, many people won't believe the truth when the government finally decides to reveal it. They'll say that it's just an excuse by the Wolfowitz camp and the neoconservatives to go to war with Iraq.
No one in the press is even asking about the Anthrax attacks. It's almost as if they never happened. Weird.