WashUStL is an excellent university. I fail to understand the level of your concern / anxiety if he is planning to apply to WashUStL RD rather than ED. (Typically recruited athletes apply ED/EA in order to receive a boost in admissions from the coach.)
At this time, which other schools are recruiting your son and which other schools are of interest to your son ?
Does your son have any particular career objective ?
Does your son want to live & work in the NE US after college or is he open to other geographic locations ?