Maybe some were taken to a nearby mosque. Others were probably dropped at relatives, or, if the kid had a relative, the cabdriver may have taken them all the way to that location. Others were helped to get a different flight somewhere.
No wonder the FBI doesn't see anything sinister in this.
Fur Shur there are ticket agents at airports who do remember dealing with a young Arabic speaking individual who needed the help of an interpreter who didn't understand the student all that well.
No doubt both the helpers and the ticket agents had difficulty buying into the idea that the kid really did want to go to Montana~!!!
They could have asked for helped getting unlost.
It is that simple.
Their first "mistake" was leaving the airport. Now, why on earth would they leave the airport if the only way to get to their school in Montana was by plane?