Authentik as a reverse proxy for VS-Code server? How

I'm currently beating my head up against Authentik. What I'm trying to do is to use Authentik to secure an unsecured service, like VS-Code server. Supposedly I can do this by pointing the domain to the Authentik server and then Authentik's proxy points to the Code Server, but everything that I try either redirects back to Authentik or just gives me a blank screen.

Authentik and VS-Code are both running on the same system in docker, with my reverse proxy on another system.

The DNS (pihole) for both code.test and auth.test point to my reverse proxy running Caddy, and all of this is running local network only.

Any ideas what I am missing? Any help would be appreciated.

---

Caddyfile:

code.test.example.com {
    tls internal
    reverse_proxy auth.test.example.com
}
auth.test.example.com {
    tls internal
    reverse_proxy 192.168.1.110:9000
}

---

Authentik Proxy Provider:

External host: https://code.test.example.com
Internal host: http://192.168.1.110:8443
Internal host SSL Validation = false

---

VS-Code Server docker-compose.yaml:

version: "2.1"
services:
  code-server:
    image: lscr.io/linuxserver/code-server:latest
    container_name: code-server
    environment:
      - PUID=1000
      - PGID=1000
      - TZ=Etc/UTC
      #- PASSWORD= #optional
      #- HASHED_PASSWORD= #optional
      - SUDO_PASSWORD=Password #optional
      #- SUDO_PASSWORD_HASH= #optional
      - PROXY_DOMAIN=code.test.example.com #optional
      - DEFAULT_WORKSPACE=/config/workspace #optional
    volumes:
      - ./config:/config
    ports:
      - 8443:8443
    restart: unless-stopped

---

Authentik docker-compose.yaml:

---
version: "3.4"

services:
  postgresql:
    image: docker.io/library/postgres:12-alpine
    restart: unless-stopped
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -d $${POSTGRES_DB} -U $${POSTGRES_USER}"]
      start_period: 20s
      interval: 30s
      retries: 5
      timeout: 5s
    volumes:
      - database:/var/lib/postgresql/data
    environment:
      POSTGRES_PASSWORD: ${PG_PASS:?database password required}
      POSTGRES_USER: ${PG_USER:-authentik}
      POSTGRES_DB: ${PG_DB:-authentik}
    env_file:
      - .env
  redis:
    image: docker.io/library/redis:alpine
    command: --save 60 1 --loglevel warning
    restart: unless-stopped
    healthcheck:
      test: ["CMD-SHELL", "redis-cli ping | grep PONG"]
      start_period: 20s
      interval: 30s
      retries: 5
      timeout: 3s
    volumes:
      - redis:/data
  server:
    image: ${AUTHENTIK_IMAGE:-ghcr.io/goauthentik/server}:${AUTHENTIK_TAG:-2023.8.3}
    restart: unless-stopped
    command: server
    environment:
      AUTHENTIK_REDIS__HOST: redis
      AUTHENTIK_POSTGRESQL__HOST: postgresql
      AUTHENTIK_POSTGRESQL__USER: ${PG_USER:-authentik}
      AUTHENTIK_POSTGRESQL__NAME: ${PG_DB:-authentik}
      AUTHENTIK_POSTGRESQL__PASSWORD: ${PG_PASS}
    volumes:
      - ./media:/media
      - ./custom-templates:/templates
    env_file:
      - .env
    ports:
      - "${COMPOSE_PORT_HTTP:-9000}:9000"
      - "${COMPOSE_PORT_HTTPS:-9443}:9443"
    depends_on:
      - postgresql
      - redis
  worker:
    image: ${AUTHENTIK_IMAGE:-ghcr.io/goauthentik/server}:${AUTHENTIK_TAG:-2023.8.3}
    restart: unless-stopped
    command: worker
    environment:
      AUTHENTIK_REDIS__HOST: redis
      AUTHENTIK_POSTGRESQL__HOST: postgresql
      AUTHENTIK_POSTGRESQL__USER: ${PG_USER:-authentik}
      AUTHENTIK_POSTGRESQL__NAME: ${PG_DB:-authentik}
      AUTHENTIK_POSTGRESQL__PASSWORD: ${PG_PASS}
    # `user: root` and the docker socket volume are optional.
    # See more for the docker socket integration here:
    # https://goauthentik.io/docs/outposts/integrations/docker
    # Removing `user: root` also prevents the worker from fixing the permissions
    # on the mounted folders, so when removing this make sure the folders have the correct UID/GID
    # (1000:1000 by default)
    user: root
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
      - ./media:/media
      - ./certs:/certs
      - ./custom-templates:/templates
    env_file:
      - .env
    depends_on:
      - postgresql
      - redis

volumes:
  database:
    driver: local
  redis:
    driver: local