It is offered 18 (g729) and 110 (type-event), however the answer only contains 18. Therefore, DTMF was not negotiated.

The access layer is the optimal trust boundary for an untrusted Cisco endpoint because it is the first layer in the network where devices connect. This layer is responsible for marking and classifying traffic for Quality of Service (QoS) purposes. Establishing a trust boundary at the access layer ensures that untrusted endpoints cannot alter QoS markings further upstream.
The core and distribution layers are deeper into the network, where traffic aggregation occurs. By this point, traffic should already be marked and trusted. Moving the trust boundary further up the network increases the risk of untrusted devices introducing incorrect QoS markings.
The WAN is an external connection to another network. The trust boundary must already be defined before traffic reaches this point to ensure consistent QoS treatment across the network.

The device details (such as model number, version, and so on) are collected from Prime Collaboration inventory and also by polling the endpoints using SNMP or HTTP.

https://www.cisco.com/c/en/us/support/docs/voice-unified-communications/unified- communications-manager-callmanager/42105-vg200-cfg.html