Anonymous participant its quite new but just go and get some proof of work. I signed my contract 2months before i applied for DTV ( via E-Visa ) and no question and additional documents asked
Just be honest. Unless he employed you to his business and make you a contract just to get DTV visa? If that's the case its okay as long as all are legal, they might ask you to show proof of work that's why they called you for interview.
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