More than likely if it isn't being created by that method, considering it is a challenge map, it is intended you get it via another method.
Unless it's a mod you added I suppose so it looks like the way to add it would be via the config folder for environmental tech by editing minable.json with something like notepad++, you'd have to learn how to write it in the correct format but that isn't too hard. You'll need the specific ore name and I'd make a backup of the .json somewhere just in case you totally fuck things up.