Chromecast over Wireguard

[mickelson]

I'm running OPNsense 25.7 on my home router and I have a working WireGuard interface. On my LAN network there's a Chromecast device. Is there a way I could start streaming to that device from an app on my phone while I'm connected to my home network over VPN? Apparently os-udpbroadcastrelay doesn't work with WireGuard at all (the service won't even start) and os-mdns-repeater doesn't work either, even though it is on.

My firewall rules are ok, I think. There are rules that allow all traffic from LAN subnet to anywhere, as well as all traffic from WireGuard subnet to anywhere.

Has anyone figured out how to make it work?