> It is, rather, that subjective experience exists (we know it exists because we have subjective experience, and whether the experience is of something invented and false does not change the fact that the experience exists).

What is in dispute here is what "subjective experience" means. If we both agree that "subjective experience" is a phenomenon that can in principle be captured by a third person objective description, then we can agree that it exists and that our observations are actually evidence of its existence.

But this is not what most people mean by this term, and it is that term that is a fiction on the eliminativist view.