This assumes it’s a raid array of 1 device
Following this guide: https://wiredverse.com/2016/06/recoving-a-synology-shr-raid-1-array-with-only-one-disk/
sudo mdadm --examine /dev/sdg5
Check the offset and insert in command below
sudo losetup --find --show --read-only --offset $((2048*512)) /dev/sdg5
sudo pvdisplay
sudo vgdisplay
sudo lvdisplay
end with (check LV Path from lvdisplay)
mount /dev/vg1001/lv /mnt -o ro
Footnote: Should probably append a folder after /mnt