After reading the seizure warrent, I'd say: not a huge deal. They target US based money supply. Even the seized banking account at Wells Fargo was only filled with Dwolla cash, which was sent to Japan. It seems Dwolla was the only critical part. As (hopefully) the other funding options (i.e. wire transfer) aren't linked to US accounts, it should be fine.
Lesson learned today: if you want to do business in the US, you have to do proper US paperwork. And tbh this isn't something unexpected.