A couple thoughts -
—I think you could safely treat Lewis and Clark as a likely. (UPS would be as well.) Acceptance rate right now is about 80% and I think he’d be a strong candidate.
—I expect you’re thinking about this, but we have some experience with it - even though first round auditions are now largely virtual, you still have callbacks etc. where you may need to be in person, and so being several hours from a major airport (like Whitman) may be a hindrance.
Outside of that concern, I think your ED candidates are great - your son might find the theater performance opportunities at Hamilton to be weaker than Vassar or Wesleyan, but more than would make up for it for outdoor attitude and activities (though I don’t think any of the ED schools are in strong snowboarding territory?), and I think is the only one on the list with an open curriculum. Hamilton and Wesleyan are both very walk-on-friendly crew programs.