A federal judge Monday declined to throw out the fraud conviction of a radio talk show host whose lawyer announced after trial that he had been diagnosed with Alzheimer’s disease.In a written opinion, U.S. District Judge Matthew F. Kennelly held Warren Ballentine III had failed to show his defense counsel bungled the job.Ballentine, who billed himself as “The People’s Attorney,” had a syndicated radio program broadcast on stations that included WVON-AM 1690 in Chicago when he was indicted in a …