Do we know what his exact testimony was in this case?

You realize it's also possible for a judge to be wrong. Why are we just assuming that the judge's opinion trumps the expert witnesses opinion on how to properly review the literature?

here were the expert defendant witnesses:

These are the five general causation experts for plaintiffs in the Tylenol MDL:

Dr. Andrea Baccarelli, MD, PhD, is a leading expert in the field of environmental health science. Dr. Baccarelli is Chair of the Department of Environmental Health Sciences at Columbia University. His research focuses primarily on exploring the chemical and molecular links between human disease and exposure to certain drugs or chemicals. He has published over 600 articles, if you can imagine. Dr. Baccarelli is an elected member of the National Academy of Medicine and he is also President of the International Society of Environmental Epidemiology Dr. Robert Cabrera, Ph.D., is an Associate Professor at the Baylor College of Medicine. Dr. Cabrera is a molecular & cellular biologist and his expertise and research focuses on chemical causes of birth defects during embryonic development.

Dr. Eric Hollander, MD, is a Professor of Psychiatry and Behavioral Sciences at the Albert Einstein College of Medicine. Dr. Hollander has been the primary investigator in numerous federal grant studies on the causes of autism. These have included several major studies on autism causes funded by the Food and Drug Administration and the National Institutes of Health. Dr. Hollander has published hundreds of scientific articles on autism and edited over 20 medical textbooks including Autism Spectrum Disorders (American Psychiatric Publishing, 2017), and the Textbook of Autism Spectrum Disorders (American Psychiatric Publishing, 2011).

Dr. Stan G. Louie is a Professor of Clinical Pharmacy at the University of Southern California. Dr. Louie’s current research and work focuses on the testing and development of new drugs for inflammatory diseases, cancer, and neurodegenerative diseases.

Dr. Brandon Pearson, PhD, is a neuroscientist and toxicologist and currently an Assistant Professor of Environmental Health Sciences at Columbia University. Dr. Pearson is an expert in neurotoxicology, epigenetics, and cell biology and he is currently involved in laboratory studies focusing on genetic and environmental factors causing autism. Dr. Pearson has never previously testified as a litigation expert but was compelled by a sense of moral duty to provide his expertise in this case.

.....

and heres the judge https://en.wikipedia.org/wiki/Denise_Cote

She received a Bachelor of Arts degree from St. Mary's College in 1968 and a Master of Arts in history from Columbia University in 1969, after which she taught U.S. history, world history, and African-American history at the Convent of the Sacred Heart, a school in Manhattan. Cote then attended Columbia Law School, where she was Notes & Comments Editor of the Columbia Law Review, and she received her Juris Doctor in 1975.[3]

Are you seriously stating that all law which has paid expert witnesses is now suspect solely because the expert is paid? Remember, Wakefield spoke garbage, paid or not. He had undisclosed conflicts of interest, his co authors retracted and the BMA withdrew his licence in the UK, his paper was retracted by the journal he published in.

The Dean was paid openly, directly, by one side of a case. As far as I know the meta analysis, which btw I do not think justifies the public health statements being made, has NOT been retracted, there are questions about methodology.

As you note, the case was lost. The judge used his discretionary powers to discount his evidence, and rightly so but the same judge will sit trial on case where he accepts the paid evidence of experts, routinely.