Autism, tourettes and ADHD, non-stimulant ADHD meds and autistic adult

Hi. I am the mom and legal guardian of my 32-year-old autistic son. He has tourette's - like tics and ADHD as well. He was diagnosed by a psychopharmacologist at Emory University when he was 12 to discern if he had ADHD or if it was just typical manifestations of autistic behaviors. He was prescribed slow release methylphenidate which worked well for almost 20 years until his slight tics became extreme causing physical pain because of intensity. After several months as it worsened we had a physician wean him off of the methylphenidate at which time the ticks lessened to a manageable degree that does not cause pain. However, his ADHD now has returned to the level of intensity that it was before medication, if not worse. His focus and attention span cause him to be significantly impaired compared to before weaning off of the stimulant. Has anyone had any similar diagnosis that was successfully treated with a non-stimulant ADHD med? Or does anyone know of a specialist such as a psychopharmacologist that is experienced with autism specifically where medications are concerned? We live near the Georgia Florida border but would travel if needed.