Most of the families I have worked with it takes about a year. There is no way to speed up the waitlist.
I know at your stage with your son a year seems like an eternity, but it goes by quickly. At the stage my daughter is at (she is an adult) I would be ecstatic if I could get service within a year.
The question is do you want to spend your child’s life waiting for various services or do you want to get on with life? You son is young and children at this age are very welcoming and want to play with everyone. Put him in regular parks and rec programs with children in his age group. Ask for a support worker with parks and rec – they don’t charge for this service only the program fee. He will learn how to play with other children, how to give and take, how to self soothe, learn new skills.