I think that's less of the issue.
As long as there is a penalty for hitting a moving ball,there will always be confusion.
The good news is for him is that the ball fell in, saving him the stroke but adding one for penalty-a wash.
Would they have actually penalized him if he had gone through the exact process and the ball had remained on the lip?
Or, worse yet, he waits his 10 seconds, realizes it won't fall, then as he's in his backswing it moves and he hits it or whiffs it (all captured on the Konicka Minolta super slow mo)