Tellingly, John Southwell died in 1654, in the middle ages. Also, you appear to admit that relics of Thomas Becket (died, 1170) are fakes (as he can't have been buried in 5 different caskets).
Circumstantially, you admit that christians (Catholics mostly) tend to venerate relics. You place the earliest date at the Crusades, which began in 1095.
You're still about a thousand years short of the goal.
You present no evidence, even circumstantial, that Jews ever venerated relics. We didn't. And Jews would have been the only people interested in Jesus at the time of his death. Nor do you present any evidence that any relic at all from 2000 years ago is authentic.
So, your vague guess about how such a thing as a shroud from 2000 years ago might have been preserved is worthy of ridicule. It is a fantasy for which no evidence exists.
In fact, all the evidence we have - from three separate 14C tests that all agreed with each other to written records of the Shroud which only go back 780 years to the shroud's residence in Italy rather than Jerusalem to our knowledge of the christian practice of counterfeiting first century relics - demonstrates a medieval origin. If you know of any direct evidence that the thing is 2000 years old, I would be happy to hear it. Jabba has proven incapable of finding any.
I do not mock your story in order to show that such a theory has no credibility (which would be an ad hom. falacy). I mock it because it has been shown to have no credibility.
No, they are not fakes (they are held by various museums Glasgow, London, France). They were designed to hold just one or two bits of bone, usually finger, so five is not an anomaly.
Historically, when the Roman empire split in two, the western side adopted the Judeo-Christianity of the then area of Jerusalem they occupied, and later ransacked, in Jesus' time. It could be said the Romans simply substituted their panapoly of Gods and Goddesses, themselves borrowed from the Ancient Greeks, hence their perceived idolotrous behaviour. For example, the worship of the Virgin Mary, touching "Holy" statues, all the pomp and circumstance of ceremony.
Whilst this might be a far cry from early Jewish worship which involves an invisible God and no "graven images", nonetheless, Christianity comes with the Abrahamic package of prophets, angels and the Messiah, with the added saints as a remnant of the old Gods and Goddesses.
It could be said the custom of Catholics collecting bones of so called dead saints is directly derived from the ancient Jewish custom of ossification, although these were collected and placed in ossuries, rather than on personal shrines.
Assume for a moment Jesus existed, was crucified, the Jewish Elder Joseph of Arimathea took the body into the Garden of Gethsemane. Whether or not Jesus rose from the dead, after a year or so, Jesus, being a practising Jew, would have had his bones collected.
Instead, we have the shroud, as of course, he didn't die and that was what was left behind in the empty tomb.
Why wouldn't Mary keep it?
As you know, Paul, formerly known as Christian persecutor, Saul, did indeed start the early church.
