If behind CGNAT and forwarding is not an option, Headscale, Tailscale or ZeroTier may be an option. I use Tailscale and it have ZERO forwarding on and can access anything on my network when connected through it. Think of these as Wireguard on Steroids. :)
Tailscale is but since you already tried them, maybe headscale that’s supposed to be the self hosted version of Tailscale that someone wrote, so you have better odds at less latency! https://headscale.net/
Zerotier? Not sure -https://www.zerotier.com/ can speak more to this.