Or more like he is running off with the coins now that their criminal activities have come to an end.
I don't believe the US will confiscate bitcoins from anyone who hasn't committed any illegal act as that would be illegal on their part.
I don't know. If Vinnik was actually involved in the criminal activities, then the chances are that Aleksey was also associated with at least some of the crimes. Anyway, he won't be able to stay aloof for too long. May be within a few days, we will hear about his arrest.