Short answer: no, you can't do that.
Longer answer: there is a setting on the OBiTALK portal page for SPx slots configured for Google Voice, that says "Use This Service for a Security Alarm Line". Checking that box tweaks the device to work with the ancient Ademco alarm communicator protocol, but it disables using Touch Tones.
Alarm companies are phasing out dial-up central station monitoring connections, given the rapid decline in landline phone use, and the degradation of the remaining copper POTS line network. Most new installations use either or both a 4G LTE modem or a IP connection via a gateway box.