A school friend of mine was in a similar situation but 30 years ago.
She got pregnant, unplanned, in a relationship during her last year doing a law degree.
He wanted her to abort, she refused.
She came from a wonderful family who supported her and she went on to finish her studies.
He had zero involvement for 5 years.
Never paid maintenance and she luckily didn't need it.
He contacted her after 5 years asking to meet.
Turns out he was engaged to a woman that was unable to have children and she was encouraging him to seek contact.
He was only doing so to humour her.
It was very stressful for her and she was hugely grateful for her legal background.
Within months they were looking for overnights and mentioned shared custody as they could provide a traditional setting.
My friend was furious as it was clearly driven by his, now wife.
She had several very very stressful years with back and forth.
After about 4 years of this they adopted a baby and they both lost interest practically overnight.
The wife was obviously busy with her new baby and he went back to being the selfish disinterested prick he always was.
They were within months down to an afternoon every couple of weeks and my friend was left with the fallout.
My point is, keep everything you have that reflects him to be the real low life he is.
You never know what can happen.
He certainly will not be telling anyone the background of your daughters birth, so keeping all correspondence will make it very easy for you to so, should the need arise.
Any guff from his family, send it on to them.
I would be absolutely devastated if either of my boys behaved this way.
Devastated, mortified and so ashamed.
Stay strong.