I'm not sure what the cost is of a lawyer to look into your case, but if it's like $100-$200 to review your declaration to see if you made a mistake you can roll back, then go for it. $8000 is a pretty steep amount and definitely worth digging into.

If that doesn't yield any progress and you have to pay $8000 no matter what, best option is to contact the state body to see if it's possible to make monthly payments. If you explain them your financial situation they should be open to it. Taking out a loan isn't the best course of action. That will only make things worse.