The former Singapore civil servant said he lost almost S$50,000 ($36,600) in the implosion of Noble Group Ltd., the commodity trading giant. He also said shareholders like him have been let down by regulators whose job it is to protect them from the sort of crisis that’s brought the company to the brink. Yet, the 71-year-old said he had no option but to vote in favor of a debt-for-equity restructuring that will hand control to senior creditors, diluting existing stockholders.