Accessing GitLab's built-in container registry without opening port 443

Question

I have a self-hosted GitLab server, accessible via https://gitlab.company_name.com (port 443)

I'm also using the container registry functionality of GitLab, accessible at https://gitlab.company_name.com:5050

I also have another Ubuntu server that I would like to run docker images on (pulled from the GitLab container registry)

The thing is, only port 5050 of the GitLab server is open to the Ubuntu server

When I try to do a "docker login gitlab.company_name.com:5050", I get an error that a connection to "https://gitlab.company_name.com/jwt/auth?..." has timed out.

Is there any way to authenticate to the container registry without opening port 443 to the Ubuntu server?

Thanks in advance!

I've tried reverse proxying and running the container registry as an insecure-registry both to no avail.