Why won't anybody answer my question?

Yes, it is a big problem and No, the legal system is not fair. I do not think there is anything you can do about it. He just needs to make the best of the time he does have with his son. I admire him for wanting to be with his son and care for him more, and I admire you for caring about your friend enough to ask this question. Never, I repeat, Never put down his mother in front of the child. One day he will be old enough to make a decision who he wants to live with and you do not want him to have any reason to reject his father.