It's always amusing when you try to Vixensplain other people's professions to them.
A precipitating event is part of a failure sequence. It is not the entire failure sequence, and differs very importantly from root cause analysis. In forensic engineering, a precipitating event has a precise definition: a point in the causal chain after which failure of a particular nature and degree becomes inevitable. For example, if you define failure as a ship foundering, the precipitating event is the point at which buoyancy becomes negative. If you define failure as a hull breach, then the environmental factor that first causes water ingress is the precipitating event. Now you can certainly go on to say that water ingress is a contributing cause of loss of buoyancy, but your failure analysis then has to be more nuanced in order to put everything correctly in perspective. JAIC offers just such a nuanced analysis. You do not, and your inability to read and understand the JAIC findings is more arrogance than curiosity.
In contrast, root cause analysis puts together all the contributing factors that apply both before and after the precipitating event. Root causes can affect the probability of a precipitating event occurring, such as ongoing maintenance failures that make parts weaker than they should be. Root causes can affect the likelihood of survival or recovery after the precipitating event, such as a failure to maintain emergency equipment or a failure to train crew to deal with emergencies.
The precipitating event in the Apollo 13 accident was the electrical arc that ignited a fire within the oxygen tank. Once that had occurred, overpressure of the tank and subsequent rupture was inevitable. The failure sequence continued for approximately two hours after that, where failure is defined as the loss of oxygen to the point of endangering mission success and human life. A root cause analysis identified design failures, testing failures, and operational failures. It also identified other singular incidents in the failure sequence—the use of heaters to accelerate venting of the oxygen during a pad test a few days earlier.
Your argument presents the straw man that the JAIC's failure sequence is non-credible because the precipitating event and the immediate result are not within the same scale. You argue that it's not credible to say that "one or two strong waves" could be enough to cause the bow visor of an ostensibly well-built, well-operated ship to fail. More insidiously, you insist that this is what your critics believe happened, no matter how much they tell you otherwise. You ignore all the root cause analysis that identifies the important contributing factors and explains why the precipitating event occurred. It did not—as you insinuate—simply happen improbably out of the blue. Your inability to understand failure mode and effects analysis hampers your judgment, sets false expectations, and therefore undermines your criticism. Your critics understand this better than you, and can see how the JAIC report properly identifes both a precipitating event and the relevant contributing factors.
In other words, you need to stay in your lane.
No, that's a simplistic understanding of the terminology.
I said an opening in the upper portion of a ship can be considered a hull breach...
I put that qualification there on purpose. For the purposes of hydrodynamics, a "hull" is only that portion below the waterline. That's because it's the only part of the hull that nominally interacts with the water. For purposes of construction and structural analysis, the "hull" is generally the part of the ship up to and including the weather deck. That's because hulls are built according to one kind of structural design and construction method and superstructures are built entirely differently. There is no One True Definition of a hull and therefore no one true definition of a hull breach.
If you need to compute a flood rate, every opening through which water is entering is considered a breach. The opening that defines a vessel's downflooding angle can be literally anywhere on the ship. For stability, you consider only the fact that the vessel is flooding. This means you need to use a different model than the metacentric height calculation you demonstrated you didn't understand. Finally, the ship's center of buoyancy is computed from the shape of the volume of displaced water regardless of what part of the ship is doing the displacing. Flooding models similarly don't distinguish between the hull as defined for other purposes and any other part of the ship as defined for those other purposes.
In other words, you need to stay in your lane.