They were caught doing it last year, they've been doing it the whole time visibly. Wings were not allowed to be below 85mm from the ground I think it was(75 above the reference plain.. which is 10mm off the ground), theirs clearly was the entire time, the tests did not reflect realistic loads, simple as that.
People take illegal steroids in sports... but pass drug tests, thus have not cheated? Is that really the argument you're going with because no one else on earth believes so. Dozens of athletes passed their drugs tests yet were found guilty of cheating years later, either via other tests on saved blood samples or investigations, confessions from others caught doing it.
Regulations and the tests aren't the same thing, the regulations were pretty clear, it was pretty obvious RBR broke them, the tests were plainly not good enough. 100kg load when it was stated by people in the sport front wings had aero loads of 10-20 times that.... it was laughable.
There was a rule about the test is must pass and a rule about the actual functioning height of the wing. Passing the test didn't mean it was breaking the rule. RBR had a wing that would scrape along the ground yet rules which stated it had to be 85mm from the ground and immobile. We could all see it flex, the test was inadequate, they still knowingly and intentionally broke the rules. They continued to knowingly and intentional break the rules in 2014 and finally got caught doing it.