CCAI Platform integration to Twilio

I am investigating functionality of CCAI Platform. I configured web chat using web SDK suggested in the documentation. When I check requests that my client sends, I see that chat messages are coming through Twilio. But I didn’t find any information about this integration in the documentation. Could you help with the following questions:

  1. As far as I understand to integrate to Twilio a corresponding account and Conversations Service should be created in Twilio. Who manages this account and service for CCAI Platform? Is it possible to get access to the Twilio account that is used in CCAI Platform?

  2. Is Twilio the only possible option for implementing chat on CCAI Platform?

  3. In the source code of web SDK I see some logic for Nexmo. In what case Nexmo is used?