Unless they physically prevented them from leaving it was still their choice, and it comes down to the individual's choice. I've walked out of situation which I deemed risky not knowing if there would be another job available, because I thought the risk was too great, I've also seen people who ignored the danger get seriously hurt.

Managers who don't put people's lives above profit make the same risk assessment but with other people's fathers, mothers, sisters, and brothers and will have to live with that choice. Company culture also has a lot to do with management pressuring people to live dangerously.