They don't exist anymore, so that is not important, and any coins can be magically ''cleaned'' by government
They don’t exist anymore, yet you can incur in some problems if you send coins from CM directly to CEX’s. Or at least this is something I have some experience about.
Sanctions did survive the organization itself!
Is it known what happened to the Chipmixer owner? As far as I remember, he was also arrested, but is there any update on his case?
He might also seek some form of pardon or a reduced sentence, possibly by referencing the Tornado Cash case as precedent.