OK, it can be done, lots of hours wasted (do all as root)
zpool list ; zpool status ...... will only show cd
zpool import -a ; zpool status ..... and pool name will show up
DON'T use the sub-pool name shown (for anything), it is incorrect
start over with correct cmd
zpool export zroot ; zpool import (-f) zroot -R /mnt .... may/may not need -f,, -R = root
zfs list zroot ..... look for the sub-pool that has a mount point (and not already mounted)
(ls -l /mnt)
zfs mount zroot/ROOT/default ..... and there you are, make changes as needed
(all in /mnt).....then...
zfs umount -a
zpool export zroot
You can thank me later,,, and if you can make intel 9560 work.....post