Forwarding ports to other devices via Wireguard doesn't work

I’ve made wireguard tu nel out to VPS (to circumvent CGNAT). Dns server works, web server + Gitea, Jellyfin,… works. All the stuff running on my thin Ubuntu client. What doesn’t work is forwarding the RDP port to my windows machine. No firewall on the windows machine. Used to work before CGNAT got enabled by my ISP. I’ve...