I think most of us would handle this sort of thing not through light linking, but through an extra render layer. It is simply more controllable and can be passed on to another artist easily. When getting into light linking, it is hard for others to figure out what your scene is doing. My 2 cents, do it in another render layer and put all objects except for the corneas in a set with an aiMatte override.
Oh I see, great I’ll read more about that!
Also just to make sure I understand the workflow: I would end up with 2 different renders, I’d have to bring them into nuke, and mask the eye render with the matte (that includes every other objects)? or is there a way to combine the 2 render layer directly in maya?
You end up with 2 layers, yes. I imagine this is for the eye speculars, right? I’d use cryptomatte to take care of the masks, it’s what everone uses these days. This is a separate topic though, unrelated to the extra render layer. For the extra eye specular layer, the extra render layer should have an aiMatte override assigned to all objects except the corneas. This will produce a render with just the specular highlights on the corneas. Just plus it on top in Nuke.