Even if the “syndrome” (which has as many different sets of symptoms as sufferers) were to be verified to be real, it would be much more likely to be caused by simple salt than by MSG. The latter sounds scarier because of its long, science-y name, but there is no biochemical mechanism has ever been suggested by which it could have those effects.
It is interesting that all of your “symptoms” just coincidentally happen to be known side effects of ordinary garden-variety salt. It’s also interesting that the cuisines usually vilified in the MSG witch hunt also happen to be very high in salt. Several orders of magnitude higher than they are in MSG. But I’m pretty sure it’s the MSG causing it. (Just as the woman in the comments above with the high blood pressure probably has the issue because of the MSG and not salt. Because we all know high sodium intake has no effect on blood pressure.) Just in case, maybe ask those knowledgeable MDs you were mentioning, since no legitimate scientist on the planet would make the verification you refer to.