Green Card has no job involved. It's the result of meeting certain conditions.
I've been through the process (married a foreigner), never did they ask anything but biographical details for her and they only cared about my income, not where it came from. (For the form promising that she would not become a public charge.) The whole focus was on whether we really were a couple or it was just a scam to get her a green card.
this is not true. I think green card application can be submitted and approved even before work started (though this probably very rarely happens), employer just need to go through certification process(prove that job requires education and skills) and prove that there is no local competition for the job.
I've been through the process (married a foreigner), never did they ask anything but biographical details for her and they only cared about my income, not where it came from. (For the form promising that she would not become a public charge.) The whole focus was on whether we really were a couple or it was just a scam to get her a green card.