I think the argument is that if it had joined before him, he wouldn't have had the chance to build up a 30 second lead and thereby get a free pitstop.
If it had caught him straight away, he would have been bunched up with the rest of them and then gone to a pitstop and come out around 7th. And he would have been very unlikely to have made up those 7 places.
So yes, a screw up caused him to have an opportunity, however, that's the way the cookie crumbles sometimes and it made for such an interesting race.