I do not understand why the name of the suspect was announced so quickly before an official request was submitted to the State of Vietnam for his extradition or trial.
So that the manhunt can begin with the help of the public. They probably weren't able to locate him so far. You can't extradite or try someone you have not arrested yet.
And if an indictment file was prepared before the site was shut down, why was the suspect not arrested before his name was announced?
They announced his name because they need your help to locate him
Personally, I do not imagine that these guys failed to hide their identities, although their history proves how smart they are.
I recommend you have a browse through the court document to see the investigation into him (starts around page 28):
https://www.justice.gov/opa/press-release/file/1574581/downloadUnfortunately, having clearnet sites and un-encrypted emails with google/yahoo/protonmail etc means it only takes one slip up. Basically warrants for information went to numerous services from email to social media to exchanges, leading them eventually to him via different alias'. Whether he was simply involved with hosting the clearnet site, or even just a user, rather than admin, is another story though as the evidence seems to lack his direct involvement. Unlike with previous darkweb market takedowns for example, it's usually a requirement to catch the suspect "logged in" as it were, for concrete evidence.
Ie they connect him through clearnet registration to email to to recovery emails to crypto addresses to exchanges to KYC, nothing more than joining dots together with a lot of warrants for information to different service and providers. At best it's a fishing expedition and he's found not guilty of money laundering and operating chipmixer and only found guilty identity fraud imo, but don't want to speculate too much over his guilt tbh...
The problem with the smartest people is that all it takes is one human error, and it can be the start of an investigation...
I am not going to open an investigation here, and all I want to say is that things are open to many scenarios as long as Chipmixer keeps data on servers like any centralized website.
No need, the US already created one. Ideally the 60 page document would be summarised here so others can understand the claim a lot quicker.