If you mean it in the sense that one could cheat the results and not be diagnosed, then absolutely. Most of their metabolites could linked to dietary deficiency. We did have a metabolite panel done and my kid would have been a false negative.

As a parent of kid with Autism I experienced it first hand. However, instead of doing like many parents (including those with neurotypicals) we did not cave-in, but build a lot of incentive and rewards and it paid off very early. But this is my n=1, so I don't know if it is because of our parenting style or something else.