Billionaire David Einhorn’s Greenlight Capital doubled down on its pitch for new General Motors Co. dividend shares, saying the carmaker misrepresented the hedge fund’s proposal for a stock split. GM presented “a one-sided and flawed analysis” to ratings companies, Vinit Sethi, a Greenlight partner and director of research, said in a statement. Underwhelmed by GM’s returns as a shareholder since 2011, Greenlight has nominated Sethi to serve as a director, along with private-equity firm executives Leo Hindery and William Thorndike. “To ensure the GM board objectively considers our plan and to look after the best interests of shareholders, we are nominating...