Best and worst case for a unemployment insurance fraud

I was investigated for over payment of 13 weeks ($5,900) of unemployment insurance benefits. I was working and also claimed weekly benefits. I was told that I am going to be prosecuted and I talked to attorney who called the state on my behalf and also was told it could go to grand jury if the DA wants it too. The attorney wants me to pay $2000 up front and another $2000 if it goes to trial, should I get a second opinion and what is the worst case for me to happen? I have never been in trouble with the law before. I also was fired from my job after they found out what had happened.
Thank you for the advice