Colin L
Tour Winner
You can't play a provisional if the original is in a water hazard. The ball he called a provisional is actually his penalty ball for the lake ball. He is now lying three in the fairway. But it does not end there. He picked up the "provisional" (his ball in play) without any authority in the rules. This constituted moving the ball in play and incurred a penalty of one stroke and must replace the ball. R.18-2a. He did not do that and holed out with the wrongly substituted ball. (The ball he dropped for the one in the lake.) That incurred an additional two penalty strokes. R. 15-2. So in addition to his strokes he should add three penalty strokes for the hole. I probably forgot something.
We'll end up with the same score but I would disagree on the applicable rule. Acepting that his ball was known to be in the water hazard, his second ball - his so-called "provisional" - became the ball in play under R27-1 - agreed. He then dropped a third ball which became the ball in play, improperly substituted for the second. That was done before he picked up the second ball which was thus just a stray ball at the time. The only applicable rule for his substitution by a third ball was 27-1 (again!). It was played from a wrong place, incurring a 2 stroke penalty. Since it was played from a place level with his second ball, it may not be a serious breach but you'd need to know if there were any other factors to be certain.