Does your theory include a motive for this?
Yes (taken from someone else), they discovered what was on the other side of the Earth and wanted to keep it hidden.
China?
More seriously: I certainly cannot fault your creativity.
The most prominent hole in the FE theory is that Earth is subject to an entirely external set of physics. The RE theory soundly explains that the Earth operates on a law of physics that is easily applied to objects smaller, larger, near, or far to the Earth itself.
If you were not dissuaded by your beliefs, you could research some of the more easily observed phenomena associated with the RE theory, and observe them yourself.
It's highly probable that modern science operates under the assumed RE theory simply because claculations remain consistent according to it. Something as simple as predicting a meteor shower, or navigating a supposedly spherical Earth.