Plex, Broadcast, and Site-To-Site VPN

Hi, 

I use the home license for two XG firewalls. I have a Site-To-Site SSL VPN configured between my two homes. Each home network is on a different subnet. I have a Plex server at Home A, and have clients in Home B which connect to the server in Home A. Simply put, I don't wish to sign-in to Plex with a PlexPass account on my server. (I have no desire to connect my Plex server to the internet or the Plex service.) 

With computers, and most Plex applications (AppleTV, Tablets) I can usually get around the issue with some hackery, such as setting the IP of the Plex server manually in the Plex App, or in the case of the AppleTV using a DNS hack. 

Then came along the XBOX One, the plex client won't let me set the ip manually on the XBOX One Plex App, the option just isn't there.

Is there anyway I can forward broadcast traffic over the site-to-site VPN, to make Plex discoverable on my Xbox One?

Thank You