Airplay screen mirroring on AppleTV on VLAN segregated network

I have an Apple TV connected to my guest zone (VLAN segregated network). After some trial and error, based on this, I enabled airplay screen mirroring from devices on my LAN zone with the following traffic rule:

According to Apple, ports 49152-65535 on tcp correspond to Xsan network filesystem. So I guess that is what screen mirror uses albeit on udp not tcp?? Does it REALLY need ~17,000 ports open ports to do this?

I am not sure, i had a kind of similar problem (printing to a printer from an ipad on different VLAN).
I had to install the avahi service:

I think the reflector takes care of al the traffic...

I am also able to use my ipad to do airplay to my apple tv.

i also have the following firewall rule.

Yes, avahi is needed to traverse the VLANs and a similar traffic rule is needed for that (see my screenshot above).