We are big fans of Dr. Black and our DS was evaluated by him in second grade. We are going back for another eval in preparation for middle school at 10 yo and in 5th grade.
DS has ASD/ADHD, very smart, does very well at school fully mainstreamed, no behavioral issues, has friends - popular and never bullied, and a happy kid: Most of the credit goes to our school and Dr. Black - DS is very well supported by his IEP which has all of Dr. Black's recommendations from the neuropsych eval.
In the past, we've used a very well known and respected developmental pediatrician and a very well known educational consultant plus other therapists and I will say that Dr. Black was and is the best money we ever spent for any provider for our DS. Definitely worth the money in our son's case.
That said, if we were not using Dr. Black we would go to Children's and use either Lauren Kenworthy or Laura Anthony for a neuropsych eval. They are both here:
https://childrensnational.org/research-and-education/center-for-neuroscience-research/research-areas/autism-spectrum-disorders
Looks like Dr. Anthony may have left.
Good luck!