I was really interested in the physics calculations, but let's have a look at the amazingly silly "probability" claim.
Generous? Based on what calculations? If you cannot provide such calculations (and I know you cannot), then the probability remains 100%.
As an aside, unrelated to numbers, keep in mind that although to most people the collapse of the south tower was a surprise, after it collapsed the collapse of the north tower was expected. That's why the evacuation order was given.
The government experts, all of them, plus private experts who were on the scene, agreed that WTC 7 was in danger of imminent collapse. That's why the evacuation order was given. Will you finally read my paper, Jessica?
Therefore, since the numbers you started with are complete bunk, your "probability" calculation is complete bunk. Agreed?
Russell, your physics please.