Gellert Bleinheim
From Witcher Wiki
Gellert Bleinheim, known at least to Jethro as the "drug lord", (and most likely Roland's brother) appears to head up the fisstech production operation for Salamandra in the Sewers of Vizima. This lab is guarded by two thugs and requires a password (or some other form of persuasion) for entry.
He and his thugs are found at the southernmost accessible part of the sewers (where they tunnels form a "Y"). He also holds the Key to the Salamandra Code, which is necessary to decipher an encrypted document recovered as part the Diplomacy and Hunting quest.
