Provisional ball penalty area?

I have the following question about the penalty area and provisional ball: I know the penalty area when I play the shot, but I cannot see the exact point where the ball crosses the penalty area (and neither can any other player). With the argument of not delaying the game unnecessarily and because the crossing point is not known, I play a provisional ball from the same spot.

1) If I subsequently find the first ball in the penalty area playable or can fix a crossing point with a high probability, I pick up the provisional ball.

2) If I can find the first ball in the penalty area but cannot play it but can fix a reference point, I also pick up the provisional ball again.

3) If I cannot find the first ball and cannot fix a reference point, the provisional ball becomes the ball in play.
Are these procedures in accordance with the rules?

Basically, if it is "known or virtually certain (95%)" that the ball came to rest in the penalty area, no provisional ball may be played; this "provisional ball" is in play.

A provisional ball may be played if it is not known or virtually certain that the original ball came to rest in a penalty area (e.g. if it may be lost outside the penalty area, out of bounds, high grass, trees in front of a penalty area).

Point of entry: In rule 17 precisely defined as interpretation I must determine the point of entry to the best of my knowledge and belief.

Interpretation:
17.1d(3)/2 - Player drops ball at the estimated spot where the ball last crossed the boundary of the penalty area. The spot turns out to be wrong. If the point at which a ball last crossed the boundary of a penalty area is not known, a player must make a reasonable judgement to determine the reference point.

Under Rule 1.3b(2), the player's reasonable judgement is accepted even if that reference point turns out to be incorrect. However, there are situations in which it becomes apparent before the player has made a stroke that the reference point is incorrect and this error must be corrected.
Example: In counting play, it is almost certain that a player's ball is in a red penalty area. After consulting with the other players in the group, the player estimates where the ball last crossed the boundary of the penalty area. The player takes lateral relief and, starting from this reference point, drops a ball in the relief area.

Before taking a shot after the dropped ball, one of the players in the group finds the player's original ball in the penalty area at a point that makes it clear that the ball had crossed the boundary of the penalty area about 18 metres closer to the hole than the reference point that the player had estimated.

As this information became known before the player made a stroke after the dropped ball, he must correct the error in accordance with Rule 14.5 (Correction of an error in replacing, putting back, dropping or placing a ball). In doing so, the player must take into account the correct reference point under Law 17.1 and may take advantage of any relief available under that Law (see Law 14.5b(2)).


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