problem with zfs raidz3 install on an 8-disk system, can't find loader

Hi,

the context here is 
* installing from usb2 stick
* tried with FreeBSD-14.2-PRERELEASE-amd64-20241024-5ae76ff5138e-269296-memstick.img
* also FreeBSD-15.0-CURRENT-amd64-20241031-5212b9500116-273335-memstick.img

hardware is ProLiant DL380e Gen8 with 8* 4Tb seagate constellation
attached to Smart Array P440 Controller in HBA (JBOD) mode.

upon reboot:
###
Attempting Boot From Hard Drive (C:)  
BIOS drive C: is disk0                
zio_read error: 5                     
zio_read error: 5                     
zio_read error: 5                     
ZFS: i/o error - all block copies unavailable
ZFS: failed to read pool zroot directory object
  
Can't find /boot/zfsloader
Can't find /boot/loader
Can't find /boot/kernel/kernel
     
FreeBSD/x86 boot
Default: /boot/kernel/kernel
boot:
      
Can't find /boot/kernel/kernel
       
FreeBSD/x86 boot
Default: /boot/kernel/kernel
boot:

###

This is after the zfs install process runs without error.
To be safe, I made sure that before running the install, i went into
the shell prompt of the installer and ran gpart destroy -F da0 (repeated for da1-7)
to make sure they were just raw disks presented. The installer when started saw 
all the disks and allows the creation of raidz3 with all of them. but upon 
removing the usb key and cold-reset, the loader can't be found.

If it's booted to the (usb stick) installer again, then going into shell prompt,
then running 'zpool import zroot' then 'zfs mount -a', the newly-created
filesystem is seen.

But it won't boot without the usb key.

In an atempt to get round the problem, after zfs load, I made with zfs create:

zfs create zroot/boot

and copied all the stuff in /boot on the installer into zroot/boot (mounted at 
that time as /zroot/boot) and tried to boot that to no avail.

Is there a way round this?
--