You most likely have to use an actual VPN between your server at home and your VPS where you route all traffic through your VPS. Otherwise the IP the master sees will always be the shared one from your ISP.
This error was resolved by updating to a newer version of Wine, the issue seemed to be related to the Wine kernel or something in that space, I do not really know the cause of the issue, but that worked solving it.
I will make the theory that for a great while you will have to use a compatibility layer as cod games are usually a windows only title and non of them have a native linux port. Down the line we may have a docker image for hosting servers but idk when that will be released for people to use if they wish.