I was thinking about setting up my own caster but the dynamic ip and firewall stuff kept me from trying.
What is your router?
I have experience working with users who use many different types of Routers to build their NTRIP BASE Caster station with ESP32.
The way to open the Port on some Routers may not be the same.
Just tell me the name and version of the Router.
Hope I can help you success in some way with your system.