What you should also consider is, that the law enforcement can lie about the data to spread panic!
So far nobody was arrested. If they really have the data, why should they publish that they have it? If they actually have it it would be much wiser to keep quiet until you can actually make the arrests.
They want people to panic so they can trace who is taking action to hide their coins from being traced, they have not made an arrest because it's too early to do that, they have caught a big fish and it has all the keys to trace and chase these criminals.
It's not even been a month their top priority is to catch Nguyen, then they can go after to other criminals once they arrest him he will open a pandora and they can start from that.