You might consider dropping a dime on them to OSHA. Even if you extract yourself from the situation it establishes and attitude that will endanger someone at some point.
It is a sad reflection on humanity, but that may mean he never works again - it can be surprising "who knows who" across dissimilar industries - i've heard rumours of secretive "black-lists", and if they exist, it probably propagates by word-of-mouth - Director Joe of xyz tells his buddies from pqr and abc. They in turn tell 2 other people each, and so on... Before you know it, no-one will employ that person again.
I believe that in most cases companies will do more, and be more responsive, without the threat of
actual proceedings by an "authorative" body. But of course they need the possibility of the "big guns" being called-in to give them a kick-start.
Here in the UK I'm seeing "safety" as causing the biggest changes in the places where i've worked on and off for many years. Re-visiting a site after only a few months away means a re-sit through induction videos, and the inevitable multiple-choice 20 questions.
OSHA states that it is the company's duty to provide, promote, and ensure compliance with adequate LO or TO procedures. In the OP's case, the company has the obligation to treat this case with the severity it deserves, and if they try to brush it under the carpet, then that may be the time to blow some whistles.
But sadly, as soon as that happens, catch-22 again, the bush telegraph kicks into life....
It is a tricky situation, and if it happened to me, I would be wary of going at it too strong, unless of course I had been injured to the point I could not work again.
Thankfully the OP is alive and well, he's obviously been "done wrong" - and he's justifiably p1$$3d about it.
I think the paramount thing is that the company recognises that they must take whatever steps necessary to ensure such an occurrence cannot ever happen again, that's the pro-active scenario. If that means removing people who either have the wrong attitude, or simply were not trained properly, then they have to do what they have to do.
If the company cannot make that recognition, then that may well be the time to start reporting, which will induce the re-active scenario, usually involving denial and a nobody wins result.