If your issue is pointing outbound call to your carrierrs. Here's my suggestion.
Instead of using API or DB directly, ill recommend you to using monster-ui. There a opensource version from commnity contribution to manage resources/carrier here https://github.com/baloeng/monster-ui-resources
From those app you can add global carrier or resource account level to your provider.
Once your create global carrier, offnet callflow with "no_match " numbers will be here. If dont, create manually for outbound like below.