What he was suggesting was that someone managed to generate the same address as you. Not only is the probability infinitesimal, but given that you've also lost NXT and assuming they were both on the DB account then it would obviously point to DB as the attack vector.

Now, regarding Bter, on top of all the names and emails (which in all likelihood would be fakes for anyone who took the time anonymise themselves) you'd want the IP and the times the account were made and log in times (make it easier to confirm time zones). Same thing will DB - although IIRC they do automatically log the IP address of log ins. Next, do you have any idea how the thief managed to get into your DB account?