That is one of the worst Op-Eds I have read in a long time. It is anti capitalist dogma that wants to hold human progress back because the little willy massive egos on the left want to control all of humaity, and if we start going off world, they lose that control.
It is clear that nations will put regulations in place, for example, a company employing British workers would still be covered by the Health and Safety at Work Act 1974 and the Management of Health and Safety at Work Regulations 1989, as well as all the legislations that falls under these umbrella acts. International Law ceeds jurisdiction where abuses occur in International waters, and the Moon would certianly not fall under any given nation state, thus, legal action would be, well, legal.
This is not to say that other regulations should not be put in placve, but the problem you have is enforcement. Unless there was a Supranational Governing body in control on the Moon itself, or any other body, then the enforcement of any legislation from anywhere is all but impossible.