Perfectly good questions. But you leave out one more perfectly good question. The shroud is there. What do you make of it?
I don't know or care what it is - I believe that He died, He was buried, and He rose again. I believe the cross existed and that some folks think they have some of the wood from it - it matters not as the wood of the cross is irrelevant. The shroud is as vital to the Truth as an image of the virgin Mary on a piece of moldy bread is - people can make much of nothing and lose sight of what is real and important - these 'artifacts" are diversions.