Want to setup a ssh server at my parents house with Contact Energy Fibre.

I noticed their setup has a RWG Model 300 with a wireless antenna. It has the single port plugged into the AF18ACV. As I understand RWG features are not used but unsure how this works in regards with port forwarding. I am used to having the single router with PPPoE as the WAN and single LAN port at my own home.

I have port forwarded 2223 and changed my ssh server accordingly. I can access locally the ssh server (at parents house). Under the AF18ACV settings I have put in NAT rule for 2223. Also have added the server IP in the DNZ section. I disabled the LAN firewall temporary but this did nothing. I use port checking websites but never get an open port.

I am wondering if this Type 300 device blocks all incoming ports by default and there is something I need to double NAT this setup. Possibly over thinking this as I cant find anyone experiencing similar issues.