I would need to study the specifics more, but my feeling is that things may not actually have been as bad as they could look in terms of cover up or lies, at least in the specific small area I describe below. Why do I say that?
They made great example of the fuel rods having graphite tips. That this was a wholly negligent design that was a ticking timebomb. I'm not really convinced this is fair. As an engineer and one who specifically specializes in operations, I know that nothing of the scale and complexity of a nuclear reactor can be made bullet proof. Trust me, just about any engineered system you use or encounter everyday has design weaknesses, compromises, hazards and risks associated with it.
Good engineers always know the risk trades they are making with any design decision, but in cases where there is an accident, lay people can interpret those decisions with 20/20 hindsight as negligence or even wanton disregard for life. In reality, that design trade was most likely bought off on by reasoning that it would take almost preposterously abnormal reactor conditions to ever lead to it being a problem. The logic can go something like this "these fuel rods can pose a hazard if the operating conditions get to X, Y, Z. We've got methods in place to prevent those conditions, and if those conditions are happening, we've got bigger problems than graphite tips!" In other words, most hazards in a very complex system are dealt with through multiple controls (design, software, operational constraints or techniques, inter-related system designs, etc). In this case, I'm sure the procedures and rules for operating the reactor would have specifically precluded these conditions.
So in that way, their kangaroo court did have it substantially correct. The behaviors of the Diatlov in the control room were so far beyond reasonable, I was dumbfounded - and I have spent thousands of hours in control rooms very similar to that. His actions were way off the charts! The individual operators were staring what we call the error chain right in the face and didn't have the fortitude (and the plant clearly didn't have the culture) for them to call a complete halt to the operation.
I place the blame 95% on the decision to press with the safety test without a) your prime shift executing it, b) considering the new conditions created by the 10 hour delay, c) by not giving any prep time or training to the team executing the test, and finally d) by deviating from procedures and rules in place. And it doesn't take Soviet sytle communism to develop the conditions that compelled them to proceed with this test.
