He said he didn’t know he had violated the rule Couple that with the fact that the Rules Committee reviewed it while he was still playing and said there was no violation, thereby issuing a ruling, it was unknown by anyone when play concluded that there was a rules violation making and incorrect scorecard possible.
They ultimately got the ruling exactly right. Two shot penalty assessed on 15.
Ridley also addressed the issue that ignorance of the rule does not excuse it. He said that that issue didn’t apply as the Rules Committee ruled that there was no violation while he was still playing. If they had ruled it was a penalty he would have been told prior to his signing his card and he would have taken the penalty then. It was precisely because they made a ruling that there was no violation that this becomes irrelevant.