How can I do that?

Question

Computer networks

Good time)
There is a Zyxel Keenetic 4g, it works via an MTS modem. Behind the Zuhel is a DVR that you need to access.
Because MTS does not give external IPs to individuals, Zyxel is connected to the VPN server, with a check mark - "use the connection to access the Internet"
In the routing table, in order, everything first goes to the VPN, if it is disabled - through the channel from MTS.
Tracing this shows that from Zuhel himself, that from the PC behind him

The problem is the following - from the MTS mobile network (from phones) it is not possible to get a picture in the application ... everything works from other operators.
As far as I remember (know), MTS and Megafon prohibit internal peering between their users.

The DVR has 2 ports for connection, both are used - 1 for control (aka web port 80), the second for connecting and transmitting a picture, which, as I suspect, begins to be transmitted in the p2p variant ...

How to make p2p also go through the tunnel, and only then connect to the client on a mobile phone?)

VPN client, with an MTS modem - Zuhel, VPN server - Mikrotik