I answered your question using logic, not direct evidence.
By the way, you seem to have forgotten that answers to questions of science come to us as a probability. There are few if any absolutes among the answers to those kinds of questions.
My patients always wanted me to be pretty much absolute. As much as humanly possible. I always tried to stay informed so I could provide “Informed Consent” and never once did I withhold anything because I was afraid the patient would refuse if they knew. In fact that is exactly how y ou get into trouble.
100% is pretty absolute. More than the alcohol by that name for sure.