I also had a person do that in my flight on the last day a few years back.
He was to ride with me however when I got to my cart there was another player sitting there and told me the original player moved to play with his friends. At the time I didn’t think much of it because we all tee’d off at the same time.
I learned later he should have been DQ’d.
Well, he did in fact win the flight and went on to play in the Championship round…