Unable to connect local jitsi server from iOS jitsi-meet app from behind a NAT

We have installed a jisti server in a LAN. The server is not public. We want to connect the server from an iPad which is in a NATTed sub-network. The iPAD connects to the jitsi server in the base LAN via a proxy. We used self signed certificates. LetsEncrypt will not work in this case. When we connect the jitsi server through browser on the iPAD, the chat works fine. However, the jitsi-meet app refuses to connect with the server. However, when we put the jitsi-server and the iPad in the same network then the iOS app works fine (with self-signed certificates).

We have checked in Wireshark on the server that in case of the app running behind the NAT, there is TLS Client hello and Server Hello being done. But then the client initiates a TCP connection closure. Whereas when we connect from behind the same NAT, but through the browser from the same iPad, we see a successful cipher spec exchange and a successful chat. Of course, we have to ignore the browser warning and the trust the certificate.

We could ignore this problem with the iOS app and be satisfied with the session through the browser. However, browser on iOS (chrome or safari) is not allowing to access the front camera of the iPad. For our application viewing the front camera is a necessity.

Any help will be much appreciated as we are badly stuck. Even, if someone can suggest if we can reverse the camera while chatting in browser from iOS, that will also be of much help.