Complex sentence: Further investigation reveals that Darheel was away from Galitep on the day of the accident which infected his workers and prisoners, and as Dukat tells Sisko, Darheel is dead-half of Cardassia attended his funeral.
Split into simpler sentences: Further investigation reveals that Darheel was away from Galitep on the day of the accident which infected his workers and prisoners. Further, as Dukat tells Sisko, Darheel is dead-half of Cardassia attended his funeral.