In this case epiphenomenalism would be true (since qualia have no effect on the physical world), but the correlation would not be a coincidence (since the physical world directly causes qualia).

But the nature of the experiences we claimed to have would not depend in any way on the properties of these hypothetical 'qualia'. There would be no event in the physical world that would be affected by them - they would not, in fact, exist.

Epiphenomenalism is never true, because it contains a contradiction in terms.