Maryland regulators have failed to ensure taxpayers are refunded hundreds of thousands in illegal fees charged by crooked mortgage lenders, according to a state-sponsored audit. The Maryland Office of the Commissioner of Financial Regulation identified more than $1.5 million in illegally charged fees during fiscal 2009, but in many cases, the agency never followed through to ensure borrowers were refunded, according to an audit by the state’s independent Office of Legislative Audits. The agency blamed much of its lack of oversight on the recession.