We don't know how Ross and other dark web folks were caught, despite all the official stories. We know what the FBI _tells_ us was the security issue. However, the Snowden doc's reveal that they are instructed to construct other legitimate stories for how to implicate a criminal after the have compromised him in order to not reveal their tactics. The exact term they used in the docs escapes my memory, but we only know that Ross _was_ captured, but we have no clue how. Perhaps he had perfect op-sec, but the real security issue was a raft of 0-day attacks and then they signed up something in his name, later legally gagging him. We really have no clue.