Whose ball?

Joe Pietersen of the Stormers kicks high. Rodney So'oialo of the Hurricanes catches the ball. He starts to move but Pietersen tackles him around the thighs. So'oialo and Pietersen both stay on their  feet and players from both sides gather around round - two Stormers and three or four Hurricanes.

It is a maul. It is certainly a maul.

The maul falls to ground and the referee decides that the ball cannot be played.

He blows his whistle and gives the scrum to the Stormers, the team which did not have possession before the maul started.

But what about the catcher?

Law 17.6 UNSUCCESSFUL END TO A MAUL
(b) A maul ends unsuccessfully if the ball becomes unplayable or collapses (not as a result of foul play) and a scrum is ordered.
(c) Scrum following maul. The ball is thrown in by the team not in possession when the maul began. If the referee cannot decide which team had possession, the team moving forward before the maul stopped throws in the ball. If neither team was moving forward, the attacking team throws in the ball.
(h) Scrum after a maul when catcher is held. If a player catches the ball direct from an opponent’s kick, except from a kick-off or a drop-out, and the player is immediately held by an opponent, a maul may form. Then if the maul remains stationary, stops moving forward for longer than 5 seconds, or if the ball becomes unplayable, and a scrum is ordered, the
team of the ball catcher throws in the ball.
‘Direct from an opponent’s kick’ means the ball did not touch another player or the ground
before the player caught it.

There, look at (h).

In this case the referee ruled that the catcher was not immediately held by an opponent, that there was the fraction of a second when he could have played the ball. He had started moving before Pietersen caught him.

But it is hard to believe that this was not immediate. Nobody would have quibbled if the scrum had been given to the Hurricanes.