James Jordan Denby, an American shot down in his private plane over Nicaragua, was allowed to meet with his brother and a U.S. official in Managua. Denby had not appeared in public since he was captured by Nicaraguan troops Dec. 6. He said he had "no idea" whether he would be charged with any crimes. Denby met with his brother, William, a lawyer from Carlinville, Ill.; Enrique Meneses Pena, his Nicaraguan lawyer; Robert Swanson, an American lawyer, and Wayne Griffith, the U.S. consul in Nicaragua. Denby, 57, owns a farm in Costa Rica and has admitted giving assistance to U.S.-backed Contras fighting Nicaragua's government.