Just an update:

I took apart the turbo inlet/intake and cleaned them of the oil. It had caked up around the turbo inlet on the bottom, but surprisingly the turbo itself is it excellent shape, fins are excellent, very minimal shaft play, and no obvious leaks from seals! For almost 200k km I think that's pretty good. My guess for this oil then would be the valve cover vent tube as that is the only source I could see oil residue coming from and flowing into the turbo inlet. Is this where a catch can would connect to catch these vapors?

I also happened to snap off one of the small black nipples on the vacuum thing attached to the turbo housing, but superglue seems to have fixed that thankfully.

eric