I know it's frustrating, but he's still young and has time to get their attention.
I'd work with your local coach to get in the SPARQ circuit and others similar to it. Visiting local program camps as well. The exposure will build over the years and he'll learn how to work a camp.
If a scholarship offer doesn't come, at least the coaches will recognize him during the walk on tryouts during his freshman year and he'll get his shot then.