Whether consciousness explains anything the script leaves unexplained is an explanatory-residual test, and it acquits humans as well.
If experience is identical to the computation there is no residual by construction, and if it merely rides along there is none either.
A behavioural gap is predicted only by interactionist dualism, which nearly nobody holds.
So the test returns nothing in the one case we are sure of.
What remains is structural matching against a theory of consciousness, and no such theory is confirmed.
The bound is not missing evidence. It is a missing theory to say which evidence counts.