I just remembered a story.
If you think about Chipmixer with his paypal accounts, hosting paid with PP, Binance's account, etc...
The same thing happened to Bitcoinfog to arrest the operator. He used Lyberty Reserve, a MtGox account with his real identity, etc.
Bought hosting server with LR and BTC coming from MtGox.
Almost exactly the same errors.
(Old people, or a bit old, surely remember about Liberty Reserve?)
What I can't figure out is how can the police prove that the owner of ChipMixer.com knew the origins of the transactions?
It doesn't really matter. The fact is they consider CM as a money transmitter under the Bank Secrecy Act and he hasn't registered with FinCen and so hasn't maintained an anti-money laundering and KYC compliance program. If he did, he would have knew the origins of the transactions
Chipmixer: "I didn't know the origins"
The USA: "You didn't know because you didn't follow the laws"
(but good comparison with a war)
If you seize a server, you have no choice to have data of something. And if you're a law enforcement why should you refuse to collect data...
Unless you don't want to do your job...