That book's theories fail because it doesn't address all of the features of the Shroud. One of the failings is that the Shroud shows some of the bones and teeth below the surface of the skin.
That could not be a manifestation of bacteria on the surface of the skin, regardless of any exudations or effects they may have, unless those exudations or effects are increased over bones and teeth.
It also does not address how those exudations or effects can be directed in a collimated vertical only nature away from the body after leaving the skin. As you can see, it fails in many ways.
I can see how a bacterial coating on the skin may exude gases which may tend to discolor the cloth with a stronger colorization the closer the body is to the cloth. However, it does not explain the accuracy of the image given the nature of gas to expand to fill space available in a globular fashion, not in a linear mode. The farther away from the body, the more blurred out the any details would be from diffusion of the gas. Any detail would be lost in chaos. That is not seen at all in the Shroud. Instead we see a laser like collimation of what ever it was that created the image as it reduces its ability to impart color with distance.
Thank you. Makes sense, and I don’t want to waste time reading about a bacteria theory if it’s already been refuted by an expert. Or if the effect can’t be replicated; and I think Schwortz would know, since he’s heard it all.