The thing I find odd is the hanging about the airport bit--after allowing an hour or so denial/rage/bargaining I'd be finding my way to the Greyhound station.
Though, I've had times in my life where I have had to take a chance on job interviews that I didn't have the money to get to. I drove to Vancouver from Calgary with $20 in my pocket, borrowed $50 for a rail pass and crashed on someone's couch on the promise of an interview that wasn't even a guarantee of a job because I was so broke. I got the job and it was water under the bridge, but if I hadn't got the job, I'd have been screwed.
Nah, I'd do it like this "Since you've cancelled my return flight, and I have no means, I'll be contacting local press and seeing if they have any interest in my story. My second round of calls will be to local law firms to see if they have any interest in becoming part of case law in exchange for some pro bono work since you've left me no way to get home after my interview with me".
Trollers just like to troll.
Scammers just throw stuff out there and see if anyone bites. Asking “but why would he tweet it, why would he post to Reddit, why would he email me? Etc” all come down to: because it works.