Theo Osterkampf was supposed to have had a couple of victories on the Dviii, but I have seen articles which cast doubt on that. In any event, I don't think anyone shot down five with the dviii.
I have only heard of one confirmed kill in a Fokker E.V (as the D.VIII was originaly known) by a pilot in Jasta 6. I can't remember his name but he was kill shortly after when his E.V broke up in mid air. That was one of the reasons for grounding the type and when it was reintroduced as the Fokker D.VIII the war was almost over.