He hasn't paid her a bloomin fortune for knowing her. He is paying to help a girl abandoned by her father (only because he is forced to apparently). If the mother does not see to it that the money is used that way, then she is a jerk too.
Please cool the drama. We don't know if the kid was "abandoned" by Johnson.
Quite possible the breakup had little to do with the kid. That happens.
In any event, I wouldn't call $5,750 in child support per month for 16 years "abandonment."