Beach balls and Outside agents

It's the type of question most young referees face when they sit their examination to qualify as a lowly Level 7. "A player shoots and the ball is heading towards the goal when it hits a dog that has run onto the field of play and misses the goal. - what should you do."
For a reason that is not yet clear, referee Mike Jones seemed to forget that rule on Saturday when the foreign object was in fact a large red beach ball that played a pivotal role in Sunderland scoring what turned out to be the only goal of the game.
In terms of footballing law, it should be stated that the beach ball was not an Outside Agent (covered by Law 3) but counted as "outside interference" under law 5 of the laws of the game. An outside agent is living, while a bright red ball punched onto the pitch by a young Liverpool fan is not.
Jones should have stopped play as soon as he saw the red ball, and definitely as soon as it played a crucial part in a goal being scored. It wouldn't have mattered if the ball was already in the net. The ref can change his mind until play restarts. But, for some reason he didn't and he now faces widepsread humiliation.
So why didn't he stop play and order a dropped ball 12 yards out? Who knows? Did he simply not see the football hit the beach ball? That's possible. It was a crowded penalty area after all. Did he think Glen Johnson had actually toe-poked the beach ball out of the way? I have to confess I thought this was the case until I'd watched five or six replays.
Who knows? The only thing we do know is that Mr Jones will be refereeing in the relative obscruity of the Championship on Saturday, with only the fans of Peterborough and Scunthorpe around to throw dozens of inflatable beach balls onto the pitch!