I mean, considering "black companies" exist in the first place i doubt they really do much unless some lawsuit or huge viral social media posts call out a company or so
To be fair, there is a bit of a difference between "business has toxic and unethical (but technically legal) culture of constant overwork and exploitation" and "the Flesh Mulcher 3000 does not have anywhere near adequate safeguards installed to prevent it from mulching flesh."
The only thing I could gather was that the ghosts do not interact with Yukari, so that makes me think she is the one responsible for turning them in to ghosts
Hmm I might be over thinking this but is the Reason Yukari is all alone because she's one of the few that can avoid the grinder ghost. And Most of the factory workers are already dead since Uchida looks like the rest if them after she dies?