Even before this study was released yesterday, there was publicized dissent from advocates from the idea of a mercury etiology of neuropsychological harm. One of them came from a well known advocate, Sallie Bernard, who was invited to be a collaborator in this study. It seems that she was involved in the planning of this study, but the lead author indicated that she withdrew her support after the results began to be circulated.
That is not how science works. If you have a problem with a study design then you dissent before you begin collecting data.