Well,
@Thomas B, it looks like all the recent off-topic meanderings have been removed together with a couple of my attempts to close off the rambling and focus back on the topic.
Probably the most relevant on topic concern you are expressing is your preference for a "load path diagram" to help move the discussion forward by your preferred method. I've given some reasons why it is not practical. I'll make this one more attempt at showing why.
The status of the "on-topic" debate is that you and I are agreed that there are three plausible contributing sub-mechanisms causing the FFA of the perimeter shell identified in the OP. That means we potentially disagree with the OP inference that column buckling was the sole cause of FFA.
We also agree that, however we more clearly define those three causes and their interrelationships, the driving process was one of load re-distribution which must be a sequential process.
You want a load diagram which is a means of defining a specific situation as the (singular) process the event would follow. Load redistribution is generic. For events such as the OP event of FFA (and also the example we have quoted - the initiation stage of Twin Towers collapses) we cannot - never will be able to - specify the specific sequence of failures.
We can rigorously explain "How the first column failed" and "How that led to second column failure" and "Third" etc etc. BUT we will never know which specific column was first. So we cannot draw a specific load diagram. We can draw a generic one. I've already presented a couple of generic diagrams to explain load re-distribution.
And this is where the overriding barrier appears. Some people can readily relate a generic explanation to a specific situation or event. And some people cannot. I have zero difficulties arguing the reasons why the first columns failed. BUT I know from multiple experiences of explaining WTC collapses that as soon as I say "the first columns" many people will ask "Which column was first" because they simply cannot process a generic argument. They have to know that it was "Column Q14" or "The third column in the second row." And given the chaos of both examples of WTC events, we will never know"Which was first". << So read that and understand but don't risk going off-topic please.
So there is the bind. We will not be able to produce a valid load path diagram that is more specific than the style of generic diagram which I have already presented. And a lot of people cannot process generic answers or relate generic models to an unpredictable situation.
We can take one more step in this discussion - the one I have already identified. viz define the details of how the three mechanisms operated and how many columns each mechanism could have made vulnerable to failure. THEN, if we can establish that column buckling was NOT the sole cause - we may be able to ballpark estimate the proportion that each contributed to the collapse.