The settlement was made, hence the obligation. Trump had no legal obligation to settle, but once he settled he had a legal obligation to fulfill the terms of the settlement or risk continuation of the suit. He chose to settle, he agreed to the terms of the settlement, and had a legal obligation to carry out those terms.
The reason Trump ended up paying the settlement was because his course was primarily liable for the mistake. The course was responsible for making sure the holes were the proper distances. Mourning’s charity would be a defendant in this case that would have won.
Because the Trump Foundation wasn’t involved in the tournament or the lawsuit.
I’m not sure why you keep bringing up the Clinton Foundation. This is a thread about Donald Trump misusing charitable donations.