If there's a judgment against a debt, can it be settled?

Yes it is possible. Even after judgment, you can settle your debt for less than what you owe as per the court's order. If you can manage to get some funds from relatives or friends, you can offer that money to the creditor and settle the judgment.

I think there are debt relief organizations that can help you settle debt with a judgment.

It is recommended to settle a debt before judgment, but you can settle a debt. Most of the creditors prefer to settle a debt instead of an uncollectible judgment. They prefer to get some money instead of no money. So, talk to your creditors first. However, it is recommended to get the satisfaction of judgment letter signed by the creditors to avoid the hassle in the future.

Yes it can be settled. I have settled judgments for client is multiple payments for less than 50 percent, however It is more difficult if a garnishment order is in place and the creditor is receiving the money.