Actually that kind of anomaly is exactly how a conspiracy if proven. The SEC or FBI is never given a recording of a phone call where a bunch of people pull out agenda minutes of a meeting titled "criminal conspiracy". They find the anomaly and work backwards. In things like SEC investigations of naked shorting they never have physical evidence beforehand, they have the data afterward.
I'm sure we will see more of the data on the holding calls going forward. But the timeline is very clear:
1 - Goodell suspends Zeke when all the evidence exonerates him.
2 - Jones goes through every legal challenge and fights Goodell's contract extension.
3 - A statistical anomaly appears in penalties that punishes the Cowboys.
That kind of anomaly does not prove a conspiracy at all. It's simply fuels the fire for conspiracy theorists.
And, yes, the FBI is absolutely given a "smoking gun" in the form of recordings, documents, witness testimony, from someone or something that fills the void and links causality.
So now, based on your theory, you've got a third separate party (NFL Referee Association) that is now in cahoots with the league to
do-in the Jerry and the Cowboys?