That's terrible. Though all too often being the better person and considerate of others costs you. It takes a strong character to retain those qualities when thankless of unjust stuff like this happens, but from hat I can tell here you've done so, so fair play.

worked on a site in East grinstead, same thing 4 floors up, open lift shaft.
Also thesite manager / builder ,laid scaff.poles & boards over the void at 4 floors & had me paint the roof lantern area.
(i was a prat for doing it)
ironically got knocked for about 20k on the job( not 100% sure the amount)
i hate builders.

Kids,tired of being bothered by your pesky parents?
Then leave home, get a job & pay your own bills, while you still know everything.

im 61, have worked in buildin trade since early 80s / more or less 40 years.
ive probably got a very good book within me(if somebody ghosted it for me !)
Ive known a small guy to be held over a flat roof by 2 big guys, 6 floors up to get to a bit of facia / had a whole scaffold lifted on me while im painting, by a fork lift while the ground workers pissed themselves laughing(nearly collapsed)
went partially through a poorly boarded scaffold and still have a moody knee/ builders had ladders too short so removed sections of other ladders and tied them together to make up the height / heavy drinking on sites (roof)/ a plasterers arm taken off when a dumb waiter in lift shaft was meant to be secured and fell, taking his arm off..
i could go on for literally hours.
loads of near misses too.

Kids,tired of being bothered by your pesky parents?
Then leave home, get a job & pay your own bills, while you still know everything.

Thats right blue, you always hear about the silly health and safety stories in the sun, but they do have an important role in saving workers lives, those builders would have bodies every job without them, its all about the pound note after all!The government arent to bothered because the same big building companies grease the gov wheels with donations to the CONservative party!

Was more a general point about health and safety.

Specific to this case I both feel sorry for him, and those he shot, and yet also clearly there may be legal repercussions for him or those in charge of the weapons. I have no real inclination either way to centre solely on him to absolve or blame, because that up at personal politics rather than caring about peoples lives. They are very often two different things.

I don't think the ministers actually make the rules.
It's the HSE who are independent and have saved 1000s of lives since its inception. You could argue every single business who make a mistake are financing hmg and its their fault!
I really think you should let it go now; it's goner ruin your mental health.