New York detectives returned to the Bronx on Friday without the man they had picked up in Cobb County Wednesday night for a 1991 homicide. The 38-year-old murder suspect, Raoul Desmin Cooper, is fighting extradition and now the governors of the two states will have to resolve the issue of sending him to New York to face murder charges ? a process that is usually routine. Returning on Friday would have been simpler, Bronx homicide detective Michael DePaolisa said soon after he arrived in New York Friday. "He has to come back."