We know Saddam has plenty of people under his direct control for development and deployment of chem weapons. So giving powerful weapons to renegade groups that could be used against him doesn't make much sense, even for a psychopath like Saddam!
More likely, they either developed them themselves in a lawless uncontrolled area of Iraq, or they begged borrow or stole them from the Iraqis and Saddam is trying to figure out how they got them, too.
Like someone stole part of Dr. Evil's Laaazer Beam!
You know, we can't account for all of our "research" strains of Anthrax here in this country, but that doesn't mean the US government was complicit in its dispersal.
By your own reasoning, do you think that the Anthrax Mailer developed the powder all by himself? Either he made it himself, or he got it from the government.... So either terror groups can develop WMD like Anthrax on their own, or they can be "gotten" from government stockpiles, even though that may not implicate said government in being complicit in the scheme.