Complex sentence: Fiorentini uncovers evidence that Miko was the victim of foul play, and who was responsible for stealing a small fortune from the Yakuza, a fortune now destined for Yumi upon reaching adulthood.
Split into simpler sentences: Fiorentini uncovers evidence that Miko was the victim of foul play. He discovers that Miko was responsible for stealing a small fortune from the Yakuza, a fortune now destined for Yumi upon reaching adulthood.