Not sure why I did not just start with trying a pre 6.xx.xx kernel…
Downloaded the the last 5.15.xx Linux kernel slapped it in /var/www/fog/service/ipxe/bzimage-5.15.98 updated the host kernel to bzimage-5.15.98 and BOOM 20GB/min.
Still willing to do some testing if there is anything you need from me to see if this can be fixed in 6.xx.xx.