Does this matter?

If a human would research the matter they would arrive to the same conclusion by visiting those websites. Essentially, an average person would have made the same mistake when researching unless you have access to specific dairy industry data. We might want to hold LLMs for higher standards than human, but AFAIK every LLM comed with a disclaimer "fact check yourself."

This regard Grok is the best as it gives you the source list for cross referencing yourself.