Complex sentence: Some sources indicate that Biwott was extremely rich, he could sometimes forget to visit his own business for four years in Amsterdam, and he was not able to enlist the properties he owns in Kenya and abroad.
Split into simpler sentences: Some sources indicate that Biwott was extremely wealthy, he could sometimes forget to visit some of his own business in Amsterdam for four years. And he was not able to enlist the properties he owns in Kenya and abroad.