Realistically, the whole bill for the kid is maybe one film paycheck, I'm sure there's all sorts of stipulations, etc.... about how she can act and his parental rights, etc.... He's getting away cheap, and he's 83 years old, what does he care about a few mill this or that away? Only argument is how fair it is to the kid.
Al reportedly gave Beverly D'angelo a similar deal about 20 years ago, except it was for twins. She's never had a bad word about how he handled the whole thing. Apparently, Pacino is very fair and doesn't want any bump roads when it comes to his kids.