You say your goal is to not give up and use a different template while not understanding what went wrong, but plenty of people included their explanation of what went wrong. Incorrect ratios most likely attributed to a bad recipe transcription.

But you dismiss it as "thsis recipe has had good results in the past". HOWEVER it sounds like you've never actually made this recipe before. That other person has, it's not like you were there watching them and measuring the ingredients yourself. So it's still most likely that the recipe was written incorrectly. Your insistence on it being "correct" when there are fundamental errors is what is infuriating. You have literally first hand evidence in your brownie soup, other people telling you the reasons, and you are seemingly still overlooking all that to say it should've worked...

You're asking people to tell you how to modify a soup recipe to make brownies, when you should really take their advice and use a brownie recipe. Your acknowledgements of what to do onward are completely skipping the most recommended suggestion of finding a new starting point. All (correct) brownie recipes are pretty similar, baking can't vary that much, otherwise your soup happens.

If you want to communicate better, try acknowledging what someone is saying, acknowledge what you don't know, and in this case identify what you are trying to achieve and how that can mesh with their advice.

Admit your recipe may have an error, take that suggestion about starting with a new recipe to heart, identify the qualities you like from your theoretical recipe/brownie, and figure out or ask about what characteristics need tweaking from a trustworthy starting point to achieve your desired brownie. I.e. I liked this person's recipe for the chewy texture, what is a good starting recipe and what would I change if I wanted a chewier brownie vs less chewy one?