Photo Illustration by Kelly Caminero / The Daily BeastAmid its worst ratings in over a decade, CNN recently sought to reinvent its primetime strategy. But that gambit to boost viewership looks like it has failed.More than a year after firing its most-watched anchor Chris Cuomo over an ethics scandal involving his disgraced ex-governor brother, the cable-news pioneer has struggled to find a permanent replacement in the 9 p.m. time slot. Last month, the network decided to fill the pivotal hour wit