You seem to be hung up on dating but not looking at the fact that something like the Shroud was beyond the capabilities of the period. They knew nothing about biology or photography (the image is a negative).
“In 1989, the results of the shroud dating were published in the prestigious journal Nature: between 1260 and 1390 with 95% certainty. But for thirty years, researchers have asked the laboratories for raw data. These have always refused to provide them. In 2017, a legal request to the British Museum, which supervised the laboratories. Thus, I had access to hundreds of unpublished pages, which include these raw data. With my team, we conducted their analysis. Our statistical analysis shows that the 1988 carbon 14 dating was unreliable: the tested samples are obviously heterogeneous, [showing many different dates], and there is no guarantee that all these samples, taken from one end of the sheet, are representative of the whole fabric. It is therefore impossible to conclude that the shroud of Turin dates from the Middle Ages.”
To reiterate: The Shroud also possesses photographic-negative properties first discovered in 1898, that on the “positive image” clearly show every gruesome, agonizing, torment endured by the “man.”
Additionally, the Shroud displays three-dimensional “distance information” resembling a topographical map but within the cloth’s two-dimensional image of the man. Furthermore, the image depth measures only two micro-fibers with no variation (such consistency is a feat impossible with human hands). And more unusual, the image does not penetrate the cloth but sits on top.
Read more at: https://townhall.com/columnists/myrakahnadams/2019/07/21/shroud-of-turin-new-test-concludes-1988-medieval-hoax-dating-was-a-fraud-n2550263
Your link provides no info on the ‘last sample’.