Here is the story I'm getting:

10 years after sleeping with someone once, wages begin getting garnished from his paycheck. He goes to court to find out what the deal is and is told that he missed his court appearance and therefore is now the legal guardian of a kid whose mom apparently put him on the birth certificate but never told him. She apparently never had any contact with him during the pregnancy then she showed him the kid once after it was born and mentioned he could be the dad but refused to get a paternity test. She said the kid didn't look like him, there could be a lot of dads, and then never contacted him again. The court appointed attorney says that they sent someone to his address to subpoena him as well as put in in the paper and he didn't show up so he is the legal guardian. He says he was no longer living at the address and never read it in the paper so he never knew he was supposed to show up to court. Both the court appointed attorney as well as a private lawyer hired years later tell him that there is a loophole in the law and because he did not show up to court, he is the legal guardian and must pay child support now no matter what; even if he was to obtain a negative paternity test now. This all took place in Texas to the best of my knowledge.

This sounds insane to me. Could this possibly be true?!?

A man had a girlfriend. They weren't monagamous. They broke up, and didn't speak for 5 years. She had a child after their breakup, and the math makes it look like he is the father. But she didn't inform him that she was even pregnant. He did not know until 5 years after their breakup that she was pregnant and had a child.

So, she waited until the child was 5 years old, and then decided to get the authorities to pay child support. He claims that the child is not his, and requested a dna test. The court denied his request.

It is now 4 years later. The child is 9.

The man in question is a roofer, and is able to find work only periodically. He has had much trouble keeping up with child support, and has been before the court and punished a couple of times for it. Both times, he again requested a dna test, claiming that the child is not his. His request has been consistently denied.

He was recently arrested again for failure to pay. His court appointed attorney says that his chances of getting a dna test are almost nil. The attorney says that in Texas, at 0-3 years, they will usually grant the request for a dna test. At 3-5 years, chances are 50/50 that they will grant a request for a dna test. But at 5 years plus, the attorney says his chances of getting a dna test are close to zero.

Is there anything he can do here to get a dna test, that doesn't require money? This is a desperate situation. He has now got a wife and stepson. His wife was recently shown to have a serious medical condition, and needs him at home.
Oops. I meant to say, "she decided to get the authorities to make him pay child support".