Hello @tobydox I will try to explain it correctly.
So for example from my PC I need to connect to remotePC1 on IPrange1 port 5901 and in the same time on port 5902 where port 5902 on remotePC1 is forwarded to second network card with IPrange2 to remotePC2 where is running VNC server on port 5900.
With two or more VNC servers inside Veyon I believe it would be possible to make connection to both remotePCs where remotePC2 would act just as second screen of remotePC1. Now I am able to make only connection to remotePC1 or only to remotePC2 with forwarded port not for both at the time.
The most simple solution for this would be to connect remotePC2 to the same IP range as my PC and remotePC1 via switch (problem solved all working fine). However in my situaton this is not and will never be possible.
I hope this explanation is OK if not I will try to make it cleaner for you to understand.