You don’t know what you’re talking about.
There is a bug that prevents some people from getting the original recipe.
I have both the foul and tormented recipes thanks to getting extra base invokers going into friends quest dungeons after I had completed it. I can not get the original in WT1, WT2 or in any other way having tried numerous attempted fixes people have talked about in the bug report forum.
I can’t get the recipe other than by perhaps making a new character and doing the entire quest chain over again, which I have zero interest in doing. I’ll be done with the season journey and this season before they fix it. It is a bug. Just because you didn’t encounter it doesn’t mean it’s not affecting other people.
One of many bug report threads on the topic:
The only thing stupid here is this comment. It is a BUG even if a white item drops one time that you happened to not notice and didn’t pick up and can’t get in any other way. I personally doubt that’s the case and it seems to happen to people who did it on higher difficulties, but even if that were true, it’s still bad design and a bug.
It’s not intended. They didn’t intend for you to not get this recipe. It prevents you from crafting the item. It is a bug.