Does you employer have an office in that state or are you working at a client location? It is quite possible that an employer posting employees at offsite, out-of-state locations would not have the access to a preferred provider/HMO networks in all of those locations.
You have insurance it is just not with the same benefits as you had before; you would/should have had to register with the new plan after your transfer if a plan was offered at your new location and select new in-network physicians. In my experience, you would receive new insurance verification cards for the new plan. It seems like the responsibility was on you to confirm the transfer if it was available.
If you signed papers making the transfer and he failed to submit them, it is most likely legally his responsibility. I do not see how this translates to a law suit against your employer or allows you to not pay your medical bills. Every time you go to a new medical office, you sign an acknowledgment that the arrangement is between you and the doctor/hospital/whatever and you are ultimately responsible for payment. A law suit would likely cost more than the bills you are incurring unless they exceed $15-20,000. You are always free to consult with an attorney; if the employer is in the wrong, a letter from an attorney will often result in correction of the problem.
If you do not like the way your employer is treating you, you are free to look for a new one.
