Part 3 of the Paper Trail begins in Georgetown, so head there and you'll start off with yet another chase with Celia. This one ends up with you having to investigate a burning car, so take the necessary pictures and collect the evidence, which consists of an origami dove and a campaign picture.
Go to the designated marker to sync and then online. Things get a bit complicated here, but the only important bit of information is at the bottom of the origami dove you collected, where you get a number you can input on the DUP Intranet. Doing this will get you surveillance footage of Celia's cell.
You can look around to find two origami doves, as well as some other clues, including webs drawn on the walls with numbers. When you click on the origami doves, the third page will reveal some numbers that correspond to the web on the wall. For example, 1 on the paper might match up to 0 on the wall.
Basically, you need to do this with both doves to get two more 11-digit codes to enter into the DUP Intranet. Make sure you follow the numbers in the numerical order given to get the correct codes. The first set will give you a report with another set of numbers that can be entered for a report on Hank Daughtry.
Note: The other set of numbers will give you an actual origami piece you can print out and fold. Doing so will reveal more numbers that when put in, will play a goodbye message by Celia. That number is 93588247459 .
On the last page of the Hank report is another case number that you can put in. When you do, you should find a picture of a surveillance camera with an ID number. This is the number you need to put into Delsin's phone on the main Paper Trail page. You'll finish the mission when you do.
Your goal in the beginning of this part is to track down the hidden camera. When you get to the location, you have to find the hidden camera (similar to the side missions in the regular game) and then collect its data by getting close to it. Head to the marker to upload the data to your online profile.
When you click on the camera, you have to hack into it, which comes in the form of a mini-game. Essentially, you have a series of hexagons with colors on its borders and a number inside. You have to connect the gray hex to the other on each screen using the hexes given to you.
The only problem is that the connecting sides of the hexes must have their colors matching (see image). Gray hexes given to you are basically free ones, enabling you to connect any colors. The numbers inside mean you can move hexes to another spot, with the number decreasing for each move (0 means you can't move it). Remember you have to replace the moved hex with another if you do.
If you cannot make a move at all, then you have three chances per puzzle to Reload the hexes given to you. Provided you still have a move to perform, you can keep going, but should it come to if you have no reloads and can't do anything, click Restart to start over on that level. There is a total of SEVEN levels for this mini-game.
Once you've cleared all seven levels, you will get two options, one for a Software Patch and one for a video. Watch the video and towards the end of it, you'll get a zoomed look at the license plate of the vehicle driving away. Write this down and choose to look at the Software Patch, where you'll find another website listed in one of the notes. Go there, input the number you got and that will trigger the end of the second mission.
Start the mission and you will have to check up on Senator Winegard, so head to the marker and you'll see him getting hit by an exploding car. Now, you have the choice to either kill him or heal him, so pick your poison and then collect the two pieces of evidence at the scene (poster and origami dove). This brings the third part of Paper Trail to an end.