Don't say anything.
Upon investigation, it was indeed discovered that someone took advantage of the chaos to inject Qiao Dehou with a syringe.
Of course, due to the monitoring angle, the entire scene wasn't recorded, Fifteen inferred this based on the person's actions.
Once a suspect was identified, focusing on this person revealed many clues.
For example, during the entire chaos.
The person repeatedly reached for their lower back and kept their gaze fixed on Qiao Dehou, attempting to get close to him multiple times.
Therefore, despite lacking substantial evidence, Fifteen was convinced that this person definitely had issues.
"I investigated this person's background; they are a drug addict. They had been jailed twice before, sentenced to two years and three years respectively."
