Okay, are you sure you're an intelligence analyst? Because the answer to this conundrum is well-known and was established a long time ago.
You give them the fish and you don't provide a fishing pole or the necessary instruction for how to catch fish. That way, they eat that one and come back for more. It's kind of like how our Liberal welfare system keeps the poor dependent on the U.S. government.
Most terrorist groups, and al Qaeda is one of them, don't have the necessary intellectual capital to reverse engineer such a weapon and then produce it themselves. In all probability, they would receive it, use it, and ask for another.
I will grant you this, Saddam was smart enough not to give them a sufficient quan y with which to turn it on him. But, I am surprised you don't either know of this priniciple or, worse, don't subscribe to it.