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I have not experimented with either .45 (ACP or GAP) or .40 S&W, but I did run tests with 9mm P. I used a vise to set back bullets in three different brands of factory ammunition in 1/10 inch increments. The last batch had the bullets forced down on the powder. When fired, only a few rounds showed any signs of high pressure in the form of slightly flattened primers, and those were with the bullet forced down on the powder, much deeper than any setback could possibly cause.
I also note that for years, tens of thousands of reloaders were advised to load rifle cartridges with the bullet seated down on the powder, even compressing the charge. Other thousands seated long bullets deep into the case to get a COAL that would fit a magazine. None of these practices seems to have caused a rash of blown up rifles.
In fact, bullet setback did not seem to become a problem until Glock produced pistols with questionable cartridge case support, and other pistol makers cut feed ramps to handle weird bullet shapes. When cases burst, those makers "discovered" bullet setback to shift the blame from poor case support, a pistol problem, to bullet setback, a user problem. It would be interesting to see the chambering of the un-named .45 pistol involved in the OP's incident.
The OP shows two cases, an unfired one with setback and a blown one. Did the high pressure from bullet setback cause the burst case? I don't know; and in spite of his dramatic presentation, I suspect the OP doesn't either.
It looks to me like the result of an unsupported case head, not high pressure, or at least not high pressure alone. There are several potential causes of high pressure and burst cases. I remain skeptical that bullet setback is one of them.
Jim
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