This is the issue if for so many years you have not "made" him pay you will not make him pay now.

What happens is first, he has the right to show the judge his income and ask for a modification, that is his right.
Next it does not make any difference for a good or bad judge, GA child support is set by state law according to income. So if his income is a lot different from when the first support was issued, it will be reduced.

In fact had he already paid, and can show it should have been lower he could have recieved credit for over payment.

In Georgia often child support modification is not even appeared at, the one party submits proof of his income, and the other party is asked to submit their info ( unless one or both asks for a hearing)

Next GA has a lot of enforcement, including having him put in jail for non payment and losing his drivers license. How many times have you taken him back to court for non payment? Have you turned this into the GA child support enforcement? Is he also from GA?