I am an Australian who has a green card and is living in America. Yay!
Just marrying a US citizen does not grant him citizenship - it takes ages. Even for me, as a green card holder marrying a US citizen does not fast track my citizenship application any quicker. The process is so long and you *really* have to be on the ball with paperwork etc - which surprises me considering how these people actually are. He would've had to enter the USA and would have been unable to work for probably about 6-12 months. She would've had to support him fully. Obviously, I am assuming here, this is where the drug dealing etc would have come into play. It is interesting that they got married in Australia - I am wondering how she entered Australia and stayed such a substantial time etc.
They would have been CRAZY to leave Australia if Zahra was still sick - why would you leave somewhere where you don't need health insurance and have a great hospital system for a country with a no-hoper wife who I doubt has had a job with insurance coveragel? I say as soon as Zahra was given the all clear, that is why they left.