I'm with Rick on this one. You need a reliable 911 provider.
ProfTech is correct that you can set up other providers that do not require registration on Voice Gateways. These work only on an outgoing only basis, they are unlikely to be reliable for 911.
What do you use now? If you are using a landline, then the OBi110 can use 911 on that service via its Line Port. If you are using cell phones, then you could consider something like the Xlink device connected to the Line Port. Note - if the cell phones are taken away from the Xlink, then you lose the 911 facility from the OBi110.
How about using Voipo 911?