Is it possible to access proxmox GUI behind firewall in openwrt

Installing and Using OpenWrt
1

There are ton of videos how to install openwrt in proxmox however I need to know about proxmox in openwrt.
I use HomeAssistant that works behind firewall with all other IOT devices and is granted access to rest of network thru that firewall.
I changed my HA to VM in proxmox. However while everything is still perfectly fine with my HA I am not able to get access to proxmox GUI from main network. I did grant it access to any zone and even snat to 192.168.1.1 - basically exactly as with my HA setup.
So because only difference that I can see is fact that proxmox does decide itself the ip address and server does not see it in dhcp - does firewall rules even matter? I have very little experience with server setups so I move completely in dark here.
thanks

2

Please post

ubus call system board

from your OpenWRT device.

3 
        "kernel": "5.10.146",
        "hostname": "WRT1900ac",
        "system": "ARMv7 Processor rev 2 (v7l)",
        "model": "Linksys WRT1900AC v1",
        "board_name": "linksys,wrt1900ac-v1",
        "rootfs_type": "squashfs",
        "release": {
                "distribution": "OpenWrt",
                "version": "22.03.2",
                "revision": "r19803-9a599fee93",
                "target": "mvebu/cortexa9",
                "description": "OpenWrt 22.03.2 r19803-9a599fee93"
4

Start with upgrading to a supported release.
Then
https://openwrt.org/docs/guide-user/services/vpn/wireguard/server
And probably DDNS...