Can a man be forced to pay child support for a child that's not his in the state of NY?

I was talking with a co-worker who is going thru a bad break-up. She and this guy have been together off and on for a few years and she came into the relationship with a child. Her ex helped raise the child, told everyone it was his child, the child knows no other father and the ex’s name is on the birth certificate as the acknowledged biological father. In the state of NY can she get child support from him? He did not legally ADOPT the child so he is not an adoptive father. He actually went to court and told the judge that he is the child’s REAL father and that he didn’t want a paternity test because he knew the child was his. If I’m correct the father has about 60–90 days to dispute the paternity and after that he is considered the father no matter what. Is this the case? And if she does get support, how long is the child entitled to support if the child is severly disabled for life? I know normally child support lasts until the kid is 18–21 in New York but does that rule apply if the child is disabled?