I'm so sorry, I was very wrong about that.
Jun's Origin Mission doesn't prevent the Riots from happening.

Just make sure that you meet these requirements.

📋 Requirements for the Riots Event:

For the Riots event to trigger, you must meet the following conditions:

•   Jun must be in Advanced AI State
• 💞 Unlocked "Going out with Jun"
• 📅 Day 28 or later
• 💵 Money: More than 6,000$
• ⛪ Completed any Church Ending:
  • If you've done the "Church's Good Ending", you must progress the Church's story after Shanice returns to the church.
• 🚪 Go for a walk alone between 12:00–20:00 (0:00–8:00 PM)

Once these requirements are met, the event can trigger during your walk.