"How would they know about the two stolen passports so quickly?"
I would think because there was an immediate investigation about everyone reportedly on the plane, including - but by no means limited - to the Austrian and Italian who - as it was quickly learned, weren't on the plane, but were alive and had, according to Interpol, reported stolen passports.
The two passengers using these passports purchased tickets at the same time and those tickets were adjacent.
But while this is certainly important information that should be followed up on, it's hardly a smoking gun in terms of understanding what happened to the plane. It is not at all unlikely that a plane going anywhere from anywhere would have one or more people using stolen passports; nor does it seem strange that people using stolen passports might be traveling together.
How common is this? from the link below: "More than 1 billion times last year, travellers boarded planes without their passports being checked against Interpol's database of 40 million stolen or lost travel documents, the Lyon-based police body said: 1 BILLION TIMES! 40 MILLION STOLEN OR LOST DOCUMENTS!
Updated On: 3/10/14 at 04:45 AM