Client IP in Pi-hole + Tailscale combo

Containers in Tailscale
1

I am currently trying to run Pi-hole in my tailnet using a containerized approach. I wanted to replicate this tutorial, but since I am only able to use containers in my environment, I modified it a bit.
I am using the following compose file to link a tailscale container with a pi-hole container (the key is the network_mode: service:tailscale part):

version: '3.5'
services:
  tailscale:
    image: tailscale/tailscale
    container_name: tailscale
    hostname: pi-hole
    restart: unless-stopped
    command: tailscaled --tun=userspace-networking
    cap_add:
      - net_admin
      - sys_module
    volumes:
      - ./data:/var/lib/tailscale
      - /dev/net/tun:/dev/net/tun

  pihole:
    image: pihole/pihole:latest
    container_name: tail-dns
    restart: unless-stopped
    environment:
      TZ: Time/Zone
      WEBPASSWORD: very-secure-password
    network_mode: service:tailscale
    volumes:
      - ./pihole:/etc/pihole
      - ./dnsmasq.d:/etc/dnsmasq.d

This makes the ports 80 and 53 appear in the tailscale dashboard for the container. I am also able to add the tail IP of the container to my DNS and use it that way. The only missing part is differentiating between the clients using pi-hole, since localhost is listed for all requests in the logs. Is this due to my container based configuration or just how tailscale dns works?