Unable to cast local media to different subnet

I used to cast local mp3’s to various google devices around my house.
As well as plex and TTS and Dashboards.

I recently divided up my network with different VLANs/subnets to categorize my devices better.
I set up an IP in HA on each of the various subnets, it has no trouble discovering various devices on all networks. I also set up an Avahi Daemon for a mDNS relay.

All of my google devices are discoverable, and I can cast dashboards and plex to them just fine.
However, I am not able to cast local media / TTS.

When I go to media and browse to an MP3 and cast it to a google home, the google will chime and show media player on the screen but nothing plays.

I am at a loss as to why the media won’t play.

@MrKuenning did you ever resolve your issue? I have a similar problem