So spirit inhabits a living vessel they can see on the meat with the vessels organs. Same with a drone. But a homoculus or a dead vessel what and how can the spirit see. Is it just dual natured astral vision or can the physical potion allows sight on the physical plane?
I think the former generally, but that does make living vessels a smidgen better in one way.

What would you rule?

It'd be using astral sight if the body did not have functioning eyes. Even a corpse as a vessel has actual eyes, so in that case it'd be using that or assensing.