The result was (since they hadn't developed an acceptance criteria for PT), placing them in an indefensible position, that we all ended up agreeing that PT would be invaluable for locating any existent cracks and insufficient fusion, that would be repaired, and that indications for undercut and porosity would be referenced through a visual inspection, consistent with C-6.10 and utilizing Table 6.1.
I was satisfied with that.
We are compliant with the code, with project contract docs, and I am comfortable that the subsequent weldments will be viable.