States have attorney generals for such nonsense. I’m a licensed, bonded, and insured general contractor. And, state jaws here mandate if I foul up, clients can use the attorney general to see that I get it right. Or, they’ll pull my license. That goes for everyone with a license.
The point I’m making is check out your options with your state. If it’s remotely the same, you’ll get him back to finish if he’s in the wrong. And, it sounds like he is. And, never, ever, ever hire a contractor that isn’t licensed for the state you are having the work done in. Bonding and insurance is required by states if they have employees. And, the attorney general will send the contractor a nice little letter. Problem solved.
Never hire any contractor without a proper license. If you do, the attorney general is going to tell you that you are on your own. He has no laws dictating otherwise.