Yes it is paired. It has been working for along time. All the extensions show except the ones that I need to add as they are in 241 and up. Its connected to a DS5012D have not looked at the connections as I was only asked to change some buttons if possible. As the phone is a digital I am guessing the side car is digital. As I do not know the system that would be my best guess.

"It works on our end so it must be fine."