Once a smoke alarms is triggered it can only be cancelled via answering the call to confirm no fire danger. A CO alarm signal will often dispatch fire no matter what. It looks like our last response here was quite some time ago, in which the article you shared is a great resource for updated information. Check out also our emergency response plans for an overview of each alarm event type.
Smoke Alarm: When your Smoke alarm sounds in your home, a signal requesting fire is sent. The monitoring center will attempt to contact your first emergency contact. If no one answers, the monitoring center will request fire dispatch. Then, the monitoring center will attempt to call the emergency contacts to notify them that the fire department has been dispatched.
I hope this helps! 