OK - I'm looking backwards into his ancestors, but there are a couple of possible connections to be explored in the current family lines.
His first wife, Angie Bowie, had a relationship with punk rocker Drew Blood (aka Andrew Lipke) and while there's not much to go on for him, their daughter was born around 1980. Someone could check into her relationships, the families that she's connected to (if any) and maybe something would pan out there.
His second wife, Iman, was married twice before - once to an as yet unidenfied Somali man, once to NBA Basketball player Spencer Haywood, and once to David Bowie. I'd have to double-check her profile, but I suspect that not all those lines have been reviewed and explored yet. She has two children - one with Spencer (Zulekha Haywood - 1978) and the other with David (Alexandria Zahra Jones - 2000). I'm not sure of any connections that can be found with Spencer and Zulekha, but it's worth exploring.
I'm also hoping as I explore his ancestors that a aunt or uncle (great aunt/uncle?) will pop up with a line that can be expanded upon. I'll keep checking as I have a few already that might start bearing additional information that could lead somewhere.