I had no backup, as I always considered my MicroSD as an external storage medium for such data.
I know you're not looking for advice that would have been great before things went wrong, but... When they say to have a backup up on external storage, they don't mean make the backup and then delete the original. Then the "backup" is just the original.
Also, I don't think that microSD life expectancy is that great. I wouldn't it trust it as a sole keeper of backups.