Okay, great, we're getting somewhere. So you concede that the true number of human birth defects is on the order of 4-5 nines.
We know this because we've observed a huge sample size of human births. Meanwhile, the experiment you reference only observed a small set of planarian worm amputations. So we can't conclude there are even 4-5 nines of reliability there, let alone "100%".
Otherwise, we could simply observe a few hundred human births, observe no defects, and conclude that human births are also "100%" reliable.
In our original debate, we were both slightly wrong about the number of nines of reliability in human births. However, you are now infinitely wrong by claiming an infinite number of nines of reliability in planarian worm amputations. I don't know whether the actual number of nines is 5, or 10, or 20, but I can be certain that it's not infinity, because that would violate the laws of probability.