Let's also be clear that he solicited not one but two murders, and deposited money into bank accounts for those hits. Those transactions probably made him easier to identify as well.
Apparently not, as he used Technocash to do it. He probably used fake ID to pay a bitcoin exchanger to send the money 3rd party.
It appears he was caught because he slipped up opsec confusing real and fake identities, he was being watched by homeland security because he stupidly tried to import 9 fake IDs to his residence, and he was logging into the server with a VPN, not SSH tunneled through Tor.
http://arstechnica.com/tech-policy/2013/10/feds-silkroad-bos...