In the ObiTalk portal for your obi. Under the Device Configuration page, near the bottom of the screen is a box that is titled Phone Port Configuration Summary.
One of the lines shows "Emergency Service Call Routes to:" and the service provider number configured (if configured).
If you checked the box for "Use This Service for Emergency 911 Calls " on the SP2 service, you should see SP2 in the box for Emergency calls routed to.
Services configured in that box get the 911 dial routed to them.