It is important to understand that the "discoveries" NASA makes are things which astronomers of the past long predicted under a Round Earth model.
The unanswered question is, ...
If the Van Allen Belts don't exist, what purpose does it serve the conspiracy to make them up?
The radiation belts were predicted long before NASA even existed, as a consequence of the magnetic fields. It serves NASA to confirm the existence of such things because it fits the model astronomers already believe. It makes it all more believable.
Not quite true, James Van Allen ( University of Iowa, ) predicted them, and designed the probes that detected the radiation belts in 1958, the same year that NASA was founded.
So for your hypothesis to be true, all the associated scientific evidence and experimental data must have been faked.
In a more general sense what scientific evidence, if any, does flat earth theory permit? Is the University of Iowa in on the conspiracy as well?