Hi Jeff, the video chat is based on HTML5 WebRTC. Usually this kind of issues are due to the network topology such as NAT, Firewalls, blocked ports, etc
TURN servers are done to overcome NAT for example, but if you are on the same LAN this makes no sense because you should always be able to estabilish a direct connection without TURN, etc unless your local router is blocking in some way the connection or blocking with closed ports.
Performing a test on the demo area
https://demo.storejextensions.org/jchatsocial_enterprise/ would help to ensure that the problem is due to your network and not to some other issue going on your website.
- John