Fannie Mae was scrambling as we went to press this week to respond to allegations that the GSE failed to notify regulators about a mortgage-fraud scheme involving $21 million in bogus loans that a former Fannie approved lender ended up passing on to Ginnie Mae. According to court documents, Fannie officials discovered in 1998 that James McLean and his wife Macy McLean had sold the GSE mortgages made to nonexistent borrowers through the couples’ First…