If I understand your last paragraph correctly, the urine test said she did have lead & mercury, but the hair test said there was none? Well, that is standard procedure. The experts say that mercury & lead don't automatically show up in the hair the way other metals do. I guess the thinking is that they lodge tightly in the tissues and would find their way into the hair only after the rest of the body is heavily polluted.

As to whether or not the people who did the hair analysis are responsible or not, that would be hard to say. Ideally, they should be telling their clients that certain metals only rarely show up on the hair test. I am curious to see how this conflict will play out.