ServiceNow xMatters how to trigger notification from a custom table

I am new to working with anything xMatters so bear with me.

I want to trigger a notification on a custom table I made that extends the task table. I found this: https://help.xmatters.com/integrations/itmgmt/servicenow.htm#Extend

But I wanted to make sure I am reading it right and that my only option is to do the "ServiceNow Inbound via IntegrationHub" to be able to send notifications on record insert/update from my custom table. Currently xMatters is working fine on the Incident table. 

I just cant seem to find any other answers about this or how to do it. I tried copying and modifying existing business rules/script includes for xMatters and I haven't had luck. 

Maybe doing some kind of REST call would work but I cant seem to find anyone else talking about this. 

Thank you I appreciate any help or suggestions.