No, he's not "natural" but then again very few if anyone who actually bodybuilds is "natural". You need to define "natural". In bodybuilding it's a VERY vague term.
A nautral is someone who just trains and eats, maybe take protein and vitamins.
When anabolic pills and injections enter the picture, it is no longer natural.
Seems like the meaning of "natural" is pretty clear to me. Of course you can argue about things like creatine and pro-hormones and whether that's "natural". These are sort of in the grey area.
If you try hormones or AAS at all, you definitely should'nt call yourself natty. But of course almost nobody follows that rule.