The only remaining thing other than that you could do, is have someone else go, or go yourself, to as many of these sites as possible, and watch how the oversight staff are actually doing what they do, watch how they interact with the workers and the project, ask as many people as you can about their situation, and see if something is wrong, and how close it seems to be to your guesses/estimations. This will give you a better idea of what to do, but you'll have to make a leap of faith at some point, because there's no way to know what will happen without actually doing something.
In fact, if you did actually go out and see how the procedures are being implemented/ignored, you could eventually figure out what's missing, what's redundant, and what's just not working correctly, and why. You could change the procedures based on what you observed.
Reports are often incomplete in some way, or overlook something. Just because something is supposed to work a certain way from typical experience and typical people doesn't mean it always does work that way, or that something integral isn't being overlooked even if it seems to work on the surface. People can miss obvious potential problems, implement instructions incorrectly, ignore one thing to focus on another, etc. You have actually watch what happens to see the underlying reasons why it does or doesn't work.