Can.t finish casting to Google Home Mini

Hello again,
noob here again looking for some help. I have setup an IoT VLAN and i watched this video:
pfsense and Rules For IoT Devices with mDNS - Lawrence Technology Services & PC Pickup (lawrencesystems.com)
and i just cant seem to finish the connection to cast to a device. If i startup an app like PlexAmp and click the cast icon i can see the device i want to cast to. if i click it my google home mini will make a sound like i connected to it but in my app it will continue to cycle and say it can’t switch to the player. and it never plays the file.

my devices in this scenario are:
pfsense router/firewall
Ubiquity Edge Switch 24 port PoE 500w
Ubiquity WiFi 6 AP
Ubiquity Controller 6.0.45.0 self hosted on VM
Android Samsung Not3 20 5G phone - Connected to LAN Network
Google Home Mini - connected to IoT VLAN on AP

i can provide whatever else you may need (I hope)

thanks in advance,
Mike

It used to work well a while back when I did this video but the with the latest version of the Chromecast we recommend putting the devices that you want to case on the same network segment as the Chromecast.