@Fog_Newb It’s probably a good idea you find those other topics mentioned and post the links here so everyone can look up the context.
The 5.15.19 kernel is definitely not the very latest. But if this is working for you it’s not something I would worry about too much at the moment.
All the kernel binaries on a FOG server reside in /var/www/html/fog/service/ipxe/
. Copy the T2 kernel binary to that directory and leave it named as is. Then edit the host settings of this Mac you want to PXE boot in the FOG web UI and set this exact filename (case needs to be correct!) as Host Kernel.
While writing this I wonder if you will be able to PXE boot that T2 Mac at all. Wasn’t that an issue and the reason for creating a boot USB stick in the first place??