I did a successful test on my GL-MV1000W Brume:

  1. Set up a simple web server on a target device connected to Brume on Port 8080
  2. Did not set up Guest wifi
  3. Added VPN Policy to not use VPN for the target device’s MAC address and tested that the target device is not going through VPN
  4. Added Port Forwarding from Brume WAN to the target device LAN over TCP Port 8080
  5. Successfully accessed web server device via URL http://a.b.c.d:8080 where a.b.c.d is the WAN IP of Brume

From the Internet, you would access via the FTTH WAN Public IP, so it should forward to you GL-AP1300, then should forward to the target device.