Westminster Weekday Preschool in Alexandria is inclusive and worth checking out.

For some reason, almost all of the private special ed schools are in Maryland, and not northern VA

It may depend on what part of Maddux you are looking for in another school, but we were unable to locate a school like maddux for the pre-k age within lesser distance from DC (our starting point). We were looking for the smaller class size with the focus on language development and social skills as well as self regulation. But if you have different features/aspects of it that you think are the reason it would work, laying those out might help others suggest schools.

Dolley Madison if a primary need is speech.

Newton in Sterling, although that might also be too far away from you.

Starting in kindergarten, Auburn.

we live in Old Town and Rockville is simply too far. Any ideas would be wonderful.

Our child has developmental delays and attention issues.