I don't know exact details. One of my good friends got MDMA pressed by these guys and he knows the details of the case better than I do. He says the investigation did not start from SR but through unrelated means. The police only found they were involved with SR after seizing their computers. I don't know if the documents they found included customer shipping addresses or only usernames and the URL or what, but they definitely found unencrypted documents which is how they knew they were involved with SR.