I have reason to believe that your son has laryngopharyngeal reflux and not GERD you should go see an ear, nose, and throat doctor. This is a fairly common disorder that is difficult for a general practice doctor or an allergy doctor to diagnose.
This is a difficult diagnostic situation. The normal CT scan is reassuring but, given the persistence of symptoms, it would not be unreasonable to request that the Scan be reviewed with special attention to the mediastinum (the anatomic area between the lungs), trachea, larynx and esophagus. The details you have provided do indeed suggest that your son’s illness includes an element of laryngeal (including vocal cords) disease/dysfunction. Such dysfunction can be functional, as for example the classic, often idiopathic vocal cord dysfunction (VCD), or secondary to other diseases including, gastro-esophageal reflux (GERD), benign polyps or tumors, and infectious disease, especially viral infections – see below.) In this regard there is a condition associated with GERD, called misdirected swallowing associated with hiatal hernia. This would be consistent with both the hoarseness (secondary to aspiration) and the difficulty swallowing your son has experienced. However, these conditions are seldom associated with chest pain and chest wall tenderness, especially of the severity you describe.
If he remains symptomatic, his doctors might want to consider direct (fiberoptic) examination of his larynx and esophagus, along with a swallowing study. If swallowing has continued to be difficult for him, consultation with a GI (gastroenterologist) should also be considered,
An unlikely, but more intriguing diagnosis is a viral (Coxsackie or Entero-virus) disease called Pleurodynia, characterized by spasmodic, paroxysmal pain (often referred to as, “the devil’s grip”. Most common in adults, it can occur in children. This is an acute infection of skeletal muscle of (often of the chest wall) usually, but not always associated with fever. The pain may be either in the chest wall or abdomen. The same pain, tenderness, can often be elicited by direct pressure on the effected muscles.
You state: “More recently he has started apparent vocal chord dysfunction attacks (which are scary because he seriously can't seem to get breath). These alternate with the severe chest pain in the same area described above. He also has an added symptom that his voice is now hoarse and he has difficulty swallowing”
This makes me wonder if the chest pain might be secondary to esophageal spasm, associated with GERD leading to aspiration and vocal cord spasm. Yet another reason why direct examination of larynx and esophagus could be revealing. Finally, another diagnosis that could link the shortness of breath, stridor and difficulty swallowing could be disease of the epiglottis, either infectious or by a benign tumor, the latter most likely to occur without fever.
To summarize, I recommend consideration of direct examination of both larynx and esophagus as most of your son’s symptoms are suspicious for disease in one or both of these areas.
Good luc