This guy has no legal case. Each golf course posts a standardized legal disclaimer that indemnifies the course against any legal action resulting from being hit by golf balls in flight. This disclaimer applies to balls hit by yourself or any other golfer.
Any other arrangement and all the golf courses in America would be forced out of business.
I did not know that. I am not a golfer.
I was thinking along the lines of contributory negligence since HE hit the ball.