How does Cisco TMS set up a call with an endpoint that is registered with Cisco Unified Communications Manager and that is connected to Cisco VCS?

Cisco TMS does not use a standalone IP dialing plan for endpoints registered to CUCM - it relies on the established CUCM-VCS SIP trunk for signaling rather than direct IP dial strings.

Cisco TMS uses the SIP trunk that exists between Cisco Unified Communications Manager and Cisco VCS to route call setup to endpoints in this dual-registration scenario, allowing TMS to traverse the CUCM-VCS boundary without needing direct registration visibility - this is a supported integration model documented by Cisco for mixed-infrastructure deployments.

Cisco TMS does not strip or modify top-level domain components from dial strings passing through CUCM - call routing uses the SIP trunk without this kind of dial string manipulation.

Cisco TMS does not drop calls in this scenario - the CUCM-VCS SIP trunk integration is an explicitly supported configuration that enables TMS to successfully schedule and connect these endpoints.