A few gatekeeper scientists at CERN probably, but the vast majority of the scientists at CERN have no clue that Einstein's theories are a hoax. They just do their compartmentalized part, and trust the old results created by gatekeeper scientists that confirm Einstein's theories.
You don't understand. All these people have been doing work with the theories, designing experiments, using equipment on their own, programming equipment, etc, etc. You can't just have a few people do that. Pretty much everyone outside of pure theorists would have to be in on it. That means everyone involved in experimental design. Not just scientists as well, but also technical staff. Even if they could be tricked at CERN, they would still have done things on their own IN THIS FIELD as part of their thesis (and frankly, grad school in general where people operate lab equipment that can confirm some of this stuff).
And again, if there were gatekeepers, there's no way they'd let things get out of hand. The whole point of their existence would be to only let out what they WANT to have let out. If that meant staging an accident and killing a rebellious research team in order to maintain power, they'd do it.
You are simultaneously having your conspiracy be super-powerful and then extremely impotent. That's not consistent.