Welcome back and so sorry for the reason of reposting.
I believe that your son may need inpatient care. Perhaps extended stay, in a good facility that has one on one therapy at least 3 times a week for children. www.adventisthealthcare.com/locations/adventist-behavioral-health/services/acute-inpatient-services/#.VipQ1ys0knEwww.gundersenhealth.org/behavioral-health/child-and-adolescent-services
Hear are 2 links to get you started in researching for your son. I have no attachment to either facility, I just searched and read what they offered. I have been inpatient 5 times over the last 4 years. So I have an idea of what I would want for someone I love.
Peace and strength