Did you know which college you daughter would have been accepted into had she not gone to Deerfield? I didn't mean your kid is not smart enough, but one sample means nothing.
Did you know where those 2 kids would have ended up had they gone to Deerfield?
Here is Deerfield's college acceptance:
https://deerfield.edu/wp-content/uploads/2013/08/School-profile-2015.pdf
Show me the numbers from some public schools at about same level, and then we talk, ok?