I would pay serious money to see that scene fleshed out into a full length "Vader hunts down Jedi one by one" thriller. Give it the PG-13 rating, or even a hard R, and do it right.
It would make sense though if it was 50 years old. Kamino was operating and making clones at least that long ago, theoretically, and Yoda definitely knew about the cloning facilities.
Its only been 30 years since the fall of soviet communism...you can do a lot with propaganda. its not that unbelievable that a galactic wide blackout on the emperor's enemies is possible.