Doctor Vale served as a field agent to Luthor in his plan to turn John Corben into a powerful ally. He infected Corben with the rare Orozco's retrovirus, for which no cure existed. Vale offered to take Corben to Luthor, who staged a breakout from Stryker's. Vale never came back to Stryker's. He resigned because he was paid very well. He didn't live to enjoy it for long, however, as Luthor had the loose end tied up.
Dr. Vale is likely named after Doctor Emmett Vale, the robotics expert who created Metallo in DC Comics.