Head to the club. You can drive the limo parked there to unlock it and add to your Cars on Demand app. Hack the bouncer's phone and wait for him to move out of his position then enter the club. Once inside, open your Profiler to find Defalt. Keep Hacking the hacked phones until you find the signal source. Hack one of the cameras then hack the security router. Once you see the server, hack it.
You have to break through a complex set of security protocols. The second layout has some dummy circuits. After breaking through, hack the camera if front of Defalt. He will trigger a blackout so you have to chase him to the rooftop. [br /]
Fixers will be waiting for your at the rooftop. After killing all enemies, go to the next marker and drop down to the ground. Defalt will escape using a vehicle so run to the nearest car and chase after him. Keep him in range until you download his files completely. Once you've successfully downloaded all data, you're free to take the ******* down.