It's not an ugly fight. You file with your labor board. They hold a hearing. There's no lawyers involved. The state will collect a penalty for every day late they were in paying you.
Nothing to do with unions, that's a reference to the state labor board that oversees the labor laws. Basically, if you are someone's employee with an agreement that you will do work for compensated, but then do not receive the compensation, the state can help get your wages.
I think WalterBright was responding to what I wrote about my own experience. I think you are talking about the Inc article, where Shaikh lacked citizenship.
Labor laws are not restricted to citizens or employees. Anyone who performs "labor" for someone else is protected by labor laws. However, some types of labor laws (such as overtime restrictions or worker's comp for injuries) may be limited to specific types of workers.