General liability insurance is to cover the insured company with their customer and general public agents any damages it covers that company. It is not legal to sell that insurance coverage to another individual or company so as an independent sub contractor it is not legal to buy someone else's insurance coverage. Also if you and your prime contractor get sued on a job he will be covered and you won't as you are not his employee so this would fall under insurance fraud if this is how it is structured his insurance company may be interested in knowing this.
Worker Comp is insurance that covers employees agents injury while working and is required in all states and some states is actually ran by the state but all programs are all state regulated. The only persons to be covered under this type of insurance policy are employees. it is no legal for an employer to charge an employee for workers comp. and as a sub contractor you are not covered by another contractors workers comp each company is required to have their own or a waiver of self insured for sole proprietorships. it is not legal to re sell workers comp either. This is fraud and may have both state and federal implications.
In a work neither are legal and your prime contractor is a poor business man at best and a crook at worst. I would get your employers workers comp id and insurance company information and either contact an attorney or go to the state workers comp board and his insurance company. You are not insured or protected in any fashion and you are being ripped off. The back charges are another story.
The only way this would be legal is if you were all in business together as owners or employees….
