That woman used your boyfriend. It takes two to make a baby. She can not blame a 15 year old boy for not wanting to meet a child when he himself was a child! He seems older and wiser, and it’s obvious from your post that he really wants to meet his child (whom he has a right as her father to meet). I agree with others that he’s going to need to get in contact with a lawyer if he’s going to make any strides towards making that happen. Maybe a legal subreddit would be able to help?
This is more r/legaladvice
Go to a family lawyer. In most cases judges want the children to have contact/relationships with both parents. This woman is a monster and doesn’t deserve her child. She needs to be in jail.