They shouted at the owner
after he tried to get rid of them for merely playing slowly. Which suggests he might have already violated racial discrimination laws before they got angry. You seem to be suggesting here that the shouting was justification to kick them out, but that came after they were told to leave, not before, and the owner himself hasn't provided any better defense for that than they were playing slowly.
If someone gets angry because you were fucking with them in some manner, then them getting angry cannot be a defense for your initial fucking with them.
EDIT: to lay out the timeline, here's an excerpt from the article:
But Steve Chronister, who co-owns the course, told police the women weren't meeting the time guidelines, and delaying tee times for other golfers.
He called 911 twice.
When Northern York County Police arrived the first time, Chronister told them the women had picked up their speed and there was no need to talk to them. A few holes later, the golfers held up the course again, Chronister said.
When he approached them, the women started yelling at him -- prompting him to ask police to remove them, he told officers.
"We skipped a hole for them to speed things up even though there was no one close behind us," Ojo said.
Officers at the scene determined it wasn't a police matter and left, Northern County Regional Police Chief Mark Bentzel told CNN
Eventually the woman left on their own and no charges were filed.
Note, that he called 911
twice and that it's implied that when he approached the women and they started yelling, it was some time
after the police were first called, then left without incident. It sounds like the angry exchange part occurred some time after the first police visit for merely being slow. So we probably have three things he did. (1) called the cops on them for merely playing slowly, (2) started trying to pressure them to leave the golf course, which made them angry, and (3) called the cops on them again, using point (2) as a justification. The pattern is more consistent with the golf course manager engaging in a pattern of harassment than anything else.