If a claim is not observable, testable, measurable, and falsifiable, it is not considered scientific.
Which is why any theory that has to start with "all observations, tests and measurements made by actual peer-reviewed scientists are part of the conspiracy and therefore suspect" to swing the evidence in its favour is called a "conspiracy theory", not a "scientific theory".
Experiments to prove the Earth is flat, performed by amateur scientists with shoddy methodology, are going to tell you the Earth is flat. In other news, water is wet, and the world is round.
Where is the measurable curvature of Earth's 70% flat water?