As long as he is not abusing the child in any way, then stay out of it. It is his own daughter after all he has a right to decide how he wants to raise her. Western custody laws are often very cruel in terms of visiting rights for fathers. This is really none of your business. It is the mans daughter. Besides, girls can be more prone to abuse from their mothers boyfriends or husbands. People who grow up in single parent households in the West, almost always end up very messed up.
Also I don’t know about Pakistani citizenship law, but since her father is a Pakistani citizen I am assuming the child could automatically be considered a citizen too, if that is the case the German Embassy can’t do anything.