In Lost Judgment, you can obtain the Where is the Time Capsule? side case in Chapter 4 by speaking with the trio in Seiryo High School Courtyard. During your conversation, you’ll receive the Memo of the Code as evidence of where their time capsule is buried. You’ll have to find the “Giant’s Wheel” and “Tree with the most branches”. Follow the objective to the other side of the Courtyard to see a giant ferris wheel off in the distance. Press L3 and examine the ferris wheel then the tree to the left along the wall. A cutscene will occur. Afterwards, return to the trio of graduates. Tell them “Someone else mistakenly took it”. Look at the letter when prompted. For the next dialog option, choose all of the options (order does not matter). You’ll eventually receive the Face Sketch of Goto for evidence.
Next, head to the objective in Chinatown near the taxi and begin Target Search. Examine the girl standing in front of a restaurant then speak with her to trigger a cutscene that will complete the case.