We don't have to "provided evidence that the patches are... newer" to invalidate the test, we merely have to show that they are NOT THE SAME as the rest of the thing being tested. That has been done.
The Carbon 14 tests were performed under the assumption that every part of the Shroud was the same age and of similar composition. If this were true, then it it reasonable to infer that the sample dates would be representative of the rest of the Shroud. Since it has been PROVEN, beyond a reasonable doubt, that the samples are NOT of similar composition, the C14 dates are invalid as a generalized statement about the age of the body of the shroud.
The C14 tests have only told us that the sample that was tested has varying reported dates from 1260 (confidence 50 years) to 1390 (confidence 50 years) with the two extremes not overlapping in their degrees of confidence. That should have told the testers that there was a problem with the homogeneity of the sample.
Although the labs that did the Carbon 14 tests did impeccable work, their efforts were sabotaged before they even received the samples because of BAD SCIENCE at the sampling stage.
And I'll note that you have yet to provide a good explanation of why, 700 years ago when the shroud first amgically appeared, it was clear, but today, it is not. Why was it clear for 1300 years, then suddenly faded? The most reasonable explanation for this is... 700 years ago, it was *new*.
And when have you asked for this "good explanation"? And what do you mean by "clear"? Are you saying it was "transparent" or that it was "bright" and then "faded" by exposure?
The primary reason this needs no "good explanation" is that it is not true.
Even the earliest written documents on the shroud comment on the fact that the image cannot be seen when close to the shroud and it only becomes "clear" when one stands at a distance. Early artistic renderings of the shroud also show attempts to capture the "faintness" of the image using paint... all unsuccessfully. None depicted a "brilliantly" colored shroud.
Has the Shroud faded in the 652 years since its public display in 1352? Yes. There has been some darkening of the non-image linen as it ages. Part of the reason for this is exposure to sunlight, fire, water stains, dirt, etc., even though most of that time it was shut up in a lightless box. However, in the first centuries after its first Lirey exposition, it was displayed frequently, often weekly, and often in bright sunlight.
The prior to Lirey theoretical history of the shroud proposes that after a couple of centuries of public display in a wooden lattice-work frame with only the face visible, again in bright sunlight, it sealed in a wall as the "Image of Edessa" for around three hundred years, then is again displayed for more centuries. In 944, the "Image of Edessa" was sent to Constantinople where the inventory list (an extant document) suddenly shows the disappearance of the "image" and the appearance of "the Shroud of Our Lord." The Sermon of Gregory Referendarius, delivered on the event of the arrival of the Image of Edessa to Constantinople, in several places refers to "the figure of our Lord" while in other he mentions the "face of our Lord" which provides a tantalizing hint that the Image had been removed from its frame, and its actual nature discovered.
In the Eleventh Century, the Fourth Crusade got bogged down in Constantinople for years. After many years of waiting for the assault on the Holy Land to begin, in 1204 the frustrated soldiers went crazy and burned and sacked the Christian city, looting the Hagia Sophia where the collection of Jesus relics were kept. The shroud disappeared from all inventories.
One participant of that Crusade was a French knight by the name of Geoffrey de Charney. One hundred and fifty years later, the Shroud appears in the possession of one Geoffrey de Charny (note the spelling difference). There may be a familial relationship. If so, and if the earlier Geoffrey stole the Shroud from Hagia Sophia, it is reasonable that the family would have kept it stashed out of sight (and out of sunlight) for 150 years,
All of this is recounted to show that the Shroud has probably been kept hidden, away from damaging sunlight, for a theoretical 800-900 years. We know that in the last two centuries, expositions have been kept to a minimum with only six expositions in the 20th Century and about eight or so in the 19th.