Configure OpenVidu + External COTURN in On-Premises Environment

Hello,
Need help in configuring OpenVidu CE + OpenVidu External COTURN in on-premise

Openvidu external COTURN is installed in DMZ
Openvidu server and KMS is on Internal server (behind DMZ)

We have all the required docker images on server. We are facing one minor issue in UDP connection due to which call is not completing. Need a help to analyze the TCP dump or evaluate the architecture and resole this NAT issue.

OpenVidu version 2.22.0
OpenVidu external coturn version 4.2.6
Thank you

Please follow the instruciton over here: Allow users behind firewalls - OpenVidu Docs