Zero Trust tunnel, multiple ports on single subdomain

Hey all, I’m trying to pass through a web app that requires the use of multiple ports in order to function. I’ve been searching and tried a few things but was unable to get things to work. The only ports necessary are 443 and 20002 (NATS) but I am unable to figure out how to get this functionality working. I got the site accessible publicly but just need port 20002 to be directed to the subdomain accordingly.
Any help is appreciated!

Looking into the issue further, I’m getting the following error in the application:
{
“level”: “error”,
“error”: “address : missing port in address”,
“time”: “2024-04-03T14:10:40-04:00”,
“message”: “error getting remote address”
}