I'm particularlty interested in golf so I continue to follow this story. Sadly, the cause of this accident has never been determined.
As for Mr. Stewart's outfits, he had a contract with the NFL (American football) to wear "plus fours" with team colors and logos which changed depending on the tournaments' venues. They looked ridiculous and never caught on but when you win the US Open no one laughs at you.
Mr. Stewart had the reputation of being somewhat of a jerk until the last couple of years of his life, when he embraced Christianity and became, literally, a new man. His professional golf associates agree that he underwent a profound change and became one of the most respected players on tour.
Here's a shot of him in Miami Dolphins (GO FINS!) attire:
