The fact that the earth is round has been known far before people even knew america existed. How can you even believe that this fact is part of any government organization's disinformation program.
Also: Casey speaks only about all americans. How come that all of europe also knows that the earth is round?

The flat-earth-hype on the other hand is mostly spread in the USA AND(!) started during a time(within the last decade) where the CIA exist!

Don't you see it? All this hype about flat-earth is, unlike you believe, an essential part of the disinformation program!