The major misconception is here:
"However, for hardened rock to bend without breaking, it must undergo metamorphic changes (caused by heat, pressure, and chemically active fluids) in its mineral content and structure, including at the microscopic level. The objective of Andrew’s research was to find out if there is any evidence of the hardened Tapeats sandstone in these smoothly bent layers having been metamorphosed by the bending process."
He's got that wrong:
“All solid and liquid substances have varying degrees of strength but will deform or flow given enough time. The measure of a materials resistance to flow is viscosity. Water flows easily and therefore has a low viscosity. Honey flows much more slowly and therefore has a higher viscosity. Tar is very viscous but over time it will flow as well. We can measure properties such as density, size, weight, and time and find that they are proportional to the viscosity of a material. M. King Hubbert (1903–1989) wrote a classic article in 1945 where he demonstrated that over millions of years, the viscosity of rocks allows them to easily flow. He was able to demonstrate that by just using properties that he could measure, the rate at which sediments deform was entirely consistent with the folding over geological time. He concluded, “Without the necessity of any special hypotheses of strength much less than, or of fluidity much greater than, that of the crystalline rocks of the earth’s surface, the behavior of the earth as a whole in geologic time must be very similar to that of the ordinary viscous fluids and extremely soft muds of our everyday experience” (Hubbert 1945).”
Mitchell, SM, 2018, A Texas-Sized Challenge to Young Earth Creation and Flood Geology, Meadville, PA, Christian Faith Publishing, Inc
As a result, this folding can happen in hard rock with no metamorphosis at all.
