PRESS STORIES ON ALLEGED US AID TO IMBERT; DEATH OF COL. RAFAEL FERNANDEZ DOMINGUEZ; BUNDY'S TALKS WITH GUZMAN; CABLES 1824 AND 1830; POSSIBLE SPEECH BY JUAN BOSCH; TRIP BY "YLF" (JAIME BENITEZ); PRESS BRIEFING IN DOMINICAN REPUBLIC BY VANCE, BUNDY