Management refuses to clear invoice

My brother has been working at TMA as a contractor. The boss has been racist and demeaning and now is refusing to clear his invoice so he can get paid. What are his options? Company is in Australia and he is in a third world country. He is losing hope and thinks nothing can be done. Launched an official harassment complaint with HR and emailed the CFO. The CFO told his colleague – ” what kind of people are you recommending?” Please help