From what I understood the German state attorney ordered the account freezing not because of bitcoin directly but because they believe that the accounts got money from phishing scams. Apparently they think fiat money from phishing attacks (which they seem to think originated from Simon) landed on those bank accounts. Their only argument written in the document is a significant rise of incoming money in march (March, as in the beginning of the last rally).
Thanks! Well, if this is the reason for closing the account, at least the increased influx of money during the March rally could easily be explained. The question is whether the German authorities accept this explanation...