If he is in, make sure its for the long term. It would be much worse for him to be in her life for a while and then leave, rather then not at all. Trust me...I know from experience.
If he is not interested in being a part of her like nothing you do or say will change that sorry to say. I know how you feel about wanting her dad to be part of her life but often they are better without. I learned that the hard way with.my son's dad