True, very good point. My confidence in the claims have definitely decreased. However, I do think there is a slight distinction between these things. One is a controversial claim of fact that you basically have to take their word for ("secret operation by foreign adversary") and the others are ultimately subjective anecdotes from real individuals ("I'm suffering from something and it's affecting my life").

Even if one thinks the suffering may be psychogenic or just caused by something completely unrelated, the suffering is likely real; I find it doubtful the media or the sufferers are just completely fabricating their subjective experiences. I am distrustful of the media and distrustful of anecdotes, but in this case I trust at least that part of the story, even if it ends up basically amounting to some sort of nocebo effect from people who may have already had some unrelated neurological issues or who may be experiencing a purely psychogenic phenomenon.

There's additionally the WSJ article subject's claimed diagnosis from a neurologist, which could be just as faulty as the JAMA studies if those are indeed faulty, or could be real but could have a cause unrelated to any kind of embassy attack. But I think that, at the least, it increases the chance that the patient is experiencing something that's negatively affecting their quality of life and functioning, whatever it might be.

I'll do some more research and probably post this in another place that I know has experts on topics like these.