Comment 12 for bug 1565950

Yes, Secure Boot will not work, however, grubx64.efi happily uses grub.cfg that is placed in the same directory and you can instruct GRUB to load modules from other location, here is my config:
search.fs_uuid E495-1F0C boot
set prefix=($boot)'/EFI/ubuntu'
insmod luks
insmod gcry_sha256
cryptomount -u 739967f19770470aa0318d8b8bcdb350
search.fs_uuid 5170aca4-061a-4c6c-ab00-bd7fc8ae6030 root cryptouuid/739967f19770470aa0318d8b8bcdb350
set prefix=($root)'/root/boot/grub'
configfile $prefix/grub.cfg