Does the server renderer call the API routes via HTTP, or does it have a more direct path to fetching the same data? If HTTP, what interface does it use - loopback or the public address of the server?
In my experience this distinction has been a source of complexity in server-rendered apps that consume the same API as the client but at a different address, leading to problems like untrusted self-signed certificates, mismatching hostnames, and leaky proxy routes.
Or perhaps none of your server rendered pages even call the API directly, and you just expose it for other clients?