I think they’ve determined that the Iranians actually were asylum seekers with no other objective and that the Iranian man who bought their tickets was sort of a professional in arranging such escapes for Iranians. They don’t seem to have been involved in terrorism and it looks like it was just an unfortunate coincidence that they were on that plane.
There were a couple of other stolen passports on the flight, and then there were the five people who checked in at the airport but never showed up for the flight, so there are still mysteries relating to the passengers.
Escape? We have Iranian students at the local university.
What a perfect cover story for prospective terrorists/hijackers.