Connecting Dome Siren

Hello: I just added a Dome Siren and added it to my Base Station. It currently shows up on my phone APP under Sirens. It shows that it is online. However, on my desktop it shows up as "Turned off" (but that might be because the Alarm is currently off?). When I tested the siren (Test Siren going into Dome Siren) via the phone app - it worked. However, I thought that if I tested the base siren (via Base station) that it would trigger the Dome Siren as well. It did not. How can I be certain that the Dome Siren will work if there is a real alarm? If it says "online" does this mean it will work? thanks