After the New York City Landmarks Preservation Commission rebuffed St. Vincent's Hospital Manhattan $1.6 billion development proposal, hospital representatives said it would file an application seeking hardship status. When it grants hardship status, the commission accepts nonprofit landlords' arguments that maintenance of buildings they own interferes with their ability to carry out their charitable purpose. St. Vincent's officials want to demolish old buildings to build a 329-foot-tall medical tower in the Greenwich Village Historic District.