Cox Phone Upgrade Incompatible with Home Security System

Rather than just plugging into the nearest jack to give dial tone to the rest of the house, the Cox installer needs to connect the new telephone jack from the back of the modem to the old NIU, which should send that dial tone to the RJ 31 jack of the alarm system, which then is already connected to the rest of the house's phone jacks.  There are enough of these complaints to make me wonder how experienced Cox's installers really are.