> Falsifying the logical inverse of X is identical to verifying X.

That's exactly the point. The issue with positivist hypotheses is that you can find evidence that supports, but does not actually verify, the claim. This seems convincing until you try to flip it around. So for example if a prediction of my model is that the sun will rise tomorrow, and the sun does rise tomorrow, that seems like it supports my model. But if my model can be wrong and the sun would still rise tomorrow, then looking for the sun rise was never going to answer the question.

If you are doing a test that will actually verify X then bias doesn't matter.