Return to Hackerspace and go downstairs to automatically trigger a cutscene. After the scene, you have to find all your crew members and talk to them. It will be easy to locate them since they’ll have mission markers that will lead you to their location. After talking to all of them, head to the middle of the festival area to join the hacking challenge.
In the challenge, you have to use the drone to hack the router on top of the dragon effigy and to start the network bypass sequence. There are timed nodes that will automatically start a countdown timer as soon as you rotate it. The two nodes near the main node are such and there’s one constantly rotating node that you can’t stop so you have to time your activation of the node when it connects the data flow to that node. It will be hard to explain and probably confusing to give the solution via words so refer to the video below for the solution on how to complete the challenge.
After completing the challenge, you’ll see more cutscenes and DedSec will finally welcome a new, very talented member. A new set of missions will become available as well.