When I was in the Navy, I got a tour of duty in a staff command. While there, I submitted a point paper for a change in the rating structure. Now I was not the first person to have this idea, I'd been hearing from many people for the 14 years I had been in by then, but I was the first to submit the idea. It got a lot of attention from the Chief of Naval Operations, but before Congress would allow the Navy to implement it, it had to have an independent study.
The firm that did the independent study could not just submit the original idea, they had to modify it. When they got through with their study, it was screwed up so the Navy sent it back to them and told them to get the answer right this time. What I'm getting at is from this experience I learned that there is no such thing as an independent study. Someone is paying for it and they want their conclusions verified. They do not want the facts to get in the way.
Now to your problem. This article was based on using additives in a perfectly good engine. The claims by the producers of these products is that they allow your engine to perform better and longer. The conclusion of the article is that those products don't do that. I think most people here will agree with that.
But your engine is not performing perfectly good, so the question is will any of these additives help. That was not discussed in this article, so the article does not apply to your situation. The problem is that so many thing could be causing your problem that maybe one of these products might help, but not likely.
However, I have seen a situation like yours, a car with a noisy lifter, "fixed" by using a can of 5 minute engine flush just before an oil change. Out of many, many noisy lifters I have heard and tried this on, it only worked once.
Other things that have worked on noisy hydraulic lifters have been adjustment (where possible), rocker replacement (the noise was not the lifter) and replacement.