Considering seeing a Pediatric Nerologist

My son, Kyle is 8 3/4. He had open heart surgery at age 7 1/2 weeks. From birth until then, he was in congestive Heart Failure and improperly diagnosed. The surgery was a success. We have no proof if any damage was caused to his brain during the surgery or weeks prior. Since age 4, he has had academic delays and in Therapy with a Social worker and then Child Psychologist and Child Psychiatrist. He is now in 3rd grade with an EI certification and receives services in all academic areas, including LRC teacher, Para Pro, 100% modified curriculum. He is appx 2 years delayed in all academic areas. He certifies for SLI (Speech), receives, OT, Sensory Disorder, Math Support, Reading Specialist, Attention problem (ruled out ADD and ADHD several times and used medications). Has been tested through Clarkston Comm. Schools, IQ test. Overall IQ = 72. Woodcock Johnson test is commensurate with this score - hence ruled out a learning Disability. He has been seeing his current Child Psychologist and Child Psychiatrist for a little over 2 years. Their first thoughts were a BiPolar diagnosis -due to major violent mood swings. He's had night terrors since infancy. Taken AntiPsychotics, AntiDepressants, ADD meds, Anxiety Meds, Catapress - to lower blood pressure and allow him to sleep. Current Diagnosis: PTSD: due to "alleged" sexual abuse by father/ex-husband and verbal and physical. Also, I went though Post Partum Psychosis when his sister was born and was hospitalized off and on for two years. Kyle was age 2 1/2 when this happened and I left my ex-husband. He has had Neruopsycholist testing and the unanswered question remains focused on: There's something wrong with his though processing. I've been encouraged, then discouraged to have a Pediatric Nerologist consultation and minimal MRI to rule out some impairments. Kyle also suffers from severe Asthma and from birth on has been on many antibiotics.........he is resistant to most. I have been recently advised to push for a Cognitive Impairment Certification and change the EI as currently written in his IEP. I'm completely lost at what to do next. The school/state is limited in resources and their goal is to push the child ahead with modifications and not supply a "person" to assist and allow him to learn the material. His last year general ed teacher and LRC teacher both stated, when pulled aside, Kyle is capable of far more than within general classroom. He also is being treated for a MRSA (Mersa) staff infection. It's a multiresistant to antibiotic staff infection. His Pediatrician is now pushing the nerologist again. Any thoughts/input. A good Nerologist, what can be determined via a Nerologist, a Cognitive Impaired Certification and the environment of a self contained Cognitive Impaired classroom?? Any input is greatly appreciated!