These financial institutions will always be caught as moving those large amounts of money will always get the attention of the authorities. Sadly the fine they are paying is nothing compared to what they have earned in the manipulation of the market, they would rather pay the penalty instead of facing jail time which I think is not possible for them, they would always make the company being in a "juridical entity" as a defense from this charges. What I want to see is that this kind of justice will improve and will also cover the cryptocurrency market, as the US government has an ongoing investigation about fraudalent fake bids, volume and important data being feed to us by known crypto exchanges.
I also heard that the us government is investigating the fact of fictitious rates, but what can they do? It is impossible to prove that the bet is fictitious. All of these rates have real cryptocurrency security and from a legal point of view they are legitimate. It's going nowhere It seems to me that the exchanges themselves suffer from such rates due to lower sales volumes. They will be the first to come up with the rules of trading on the exchange to fight such manipulations.