"In many states, he would be still forced to financial take care of the child until 18 years of age..."
Not unless they are married. If they are not married, she is on her own now that it has been established that he in not the "father".
I believe that is true if he blindly signs the birth certificate forms, listing himself as the father. But it appears to me that he had "doubts" before the child was born, and had a paternity test done right after the birth.
I am just wonder why he publicly announce that the child is not his. Does he plan to dump this woman, and wanted to make sure that the gossip newspapers, can't use a Headline like, "Chris Cagle Abandons New Born"