So since 2.2h it appears fast roaming is working with WPA2 on the Apple TV’s. There’s however more issues with WPA3 as per this thread: https://forum.alta.inc/t/connectivity-issues-for-wpa3-required-after-ap-firmware-2-2h-upgrade/ that I am also experiencing but I feel the core issue with Fast Roaming is fixed.
I was also able to enable PMF (Optional) and have all devices connect no problems.
Appreciate the work!