That appeared to work for me, but now my Grub doesn’t appear to be pointing to the right one. So the new snapshots created aren’t appearing in the snapshot list in Grub, the primary boot still has the issue, but the snapshot I had booted from before and ran the command you posted still works and is now up to date. So more work for me!
UPDATE
Just to close the circle on this, I tried reinstalling and updating my grub, but it said it wasn’t using the entries by default and grub remained the same. Found another post with other sort of grub issues, but it had the resolution for my grub.