That doesn't really prove anything. I could create a Markov chain with a random seed that doesn't always answer the same question the same way, but that doesn't prove the human brain works like a Markov chain with a random seed.

One thing humans tend not to do is confabulate entirely to the degree that LLMs do. When humans do so, it's considered a mental illness. Simply saying the same thing in a different way is not the same as randomly randomly syntactically correct nonsense. Most humans will not, now and then, answer that 2 + 2 = 5, or that the sun rises in the southeast.