I'm sorry, but this would be an entire paradigm shift of how we see ourselves as a species. To think people would show up to work on monday I think is uncertain. We would be going from a millenia of human primacy on this planet to having these unknown apex predators lurking with unknown intentions. It's so completely unprecedented that it would be hard to imagine there wouldn't be social unrest, and major dissatisfaction with governments that have chosen to lie to the people they allegedly serve and represent. You might start to question who really runs the world, if some secret cabal had been able to keep the greatest secret of all time a secret for decades, and make decisions for the entire planet independent of our supposed democratic process.
If any of that were true, this "secret cabal" that really runs the world wouldn't have allowed these things to be revealed in the first place. If they did, they're either inept because they couldn't see the scenario coming that you did or they don't actually control as much as you are suggesting they would (or don't exist at all).
This just comes across as conspiracy mongering. Yes, there will be people who think like that but those people already think like that. There wouldn't be some mass collapse in society or government. The most that would happen is people would be interested in the information released, acknowledge the government has secrets just like they did yesterday, and move on with life.
