This patient support community is for discussions relating to Dysautonomia (Autonomic Dysfunction) including: Postural orthostatic tachycardia syndrome (POTS), neurocardiogenic syncope, mitral valve prolapse dysautonomia, pure autonomic failure, autonomic instability and others.
Has he seen a Neurologist? Was he given a CT or MRI at the time of his head injury? Has he had an EEG since the onset of his seizures? If not, I'd recommend asking your pediatrician for a referral to a Neurologist.
You also mentioned that he has seen a Cardiologist. Was this doctor able to offer any insight?
I wish you the best.
Here's the article: http://www.nytimes.com/2008/06/15/magazine/15diagnosis-t.html?_r=3&oref=slogin&oref=slogin
But as I read it again I realized that actually the docs down in Atlanta were stumped and ended up sending the family up to Philly. I presume the "study" the doctor ordered to confirm the diagnosis was a tilt; I don't know if they have further autonomic testing available there or not. And again, it'd be quite a hike from where you live. I'll let you know if I come up with anything closer.