You fail to think this through. The tests are invalid as the material tested has been proven to be unrepresentative of the cloth. No one can stand behind the results. Thus the tests are invalid.
We cannot, of course, say that they did not produce a proper date arrived at incorrectly. And should that be the case, that would still not make the tests valid.
I, and every shroud researcher I know, would love nothing more than to see valid tests conducted. I doubt that will happen because the Catholic church has taken a firm position that no more invasive test will be done and no more dating will be done. In fact, no tests will be done except those related to preservation.
Fortunately, some material is not under their control (although it may be their legal property). And so testing does continue. Regrettably, there is insufficient material to do perform proper carbon 14 testing. Add to that, many scientists have ethical issues in opposing the Church's stance on further dating as the material's ownership is in question.
The best we can do in realizing that the cloth is much older is to examine a preponderance of other evidence such as the Sudarium, historical records, art history, the carbon 14 error estimates from Beta Analytic, fabric science, and the discovery that the Shroud contains no vanillin (which is almost certain thermal decomposition evidence that the Shroud is not medieval).
So what can we expect your reply to be regarding the vanillin.
Shroudie