Any method to install GRUB on a Logical Volume of LVM?

I’m trying to put GRUB on a Logical Volume of LVM.

My scenario with VirtualBox is like this

I created 3 HDD: /dev/sda (10GB), /dev/sdb (5GB), /dev/sdc (3GB). The total size ~18GB.

I booted with NixOS 20.03 Live CD. I used the following commands to create 3 logical volumes: /dev/data/boot, /dev/data/root, /dev/data/swap

# Create 3 physical volumes
sudo pvcreate /dev/sda1 /dev/sdb1 /dev/sdc1
# Join all 3 into 1 big volume group named 'data'
sudo vgcreate data /dev/sda1 /dev/sdb1 /dev/sdc1
# Create 3 logical volumes
sudo lvcreate -n boot -L 500M data
sudo lvcreate -n root -L 16G data
sudo lvcreate -n swap -l 100%FREE data

Then, I set filesystem for each of them and mount

sudo mkfs.fat /dev/data/boot
sudo mkfs.ext4 /dev/data/root
sudo mkswap /dev/data/swap
sudo mount /dev/data/root /mnt
sudo mkdir /mnt/boot
sudo mount /dev/data/boot /mnt/boot
sudo swapon /dev/data/swap

I put configuration.nix into /mnt with

sudo nixos-generate-config --root /mnt

I set the following value in the file

boot.loader.grub.device = "/dev/data/root"

Then I installed the OS with sudo nixos-install

However, I got the following error

I saw this guy who reported that he successfully implements this scenario.

Could you please point out where I did wrong?