Inside the lab, kill off a couple of enemy soldiers then use the Double DP near the back door. Save your game then examine the transport in the center of the room. Choose to sit down to be transported to the 2nd floor. Once there, use the Flare DP then enter the door. Fight a couple more soldiers then peer through the window in the back, which shows little Ellone trapped inside a room. Screw around with the blue panel on the right until you see a message saying the door is unlocked. Return to the 1st floor and enter the back door to rescue Ellone.