[Update: The evidence is now against what follows, but I leave it here as a lesson in humility]
I think I am going to challenge this one. The more I study the details of these designs, the more I begin to doubt their authenticity. Call me an old cynic if you will.
First, provenance. Or rather, the lack of any. Everything on the Internet points back to Zichek's article. Even Bill Rose's mention in his Secret Projects - Flying Wings and Tailless Aircraft appears to (Publishing just 5 years later, he notes that "they remained unknown until relatively recently"). None of the drawings or renderings are verifiably by anyone else. Unless the article itself contains verifiable references (and I confess I have not seen it), there is no provenance. None.
Second, historical oddities appear in the storyline. If you are developing a continuous line of studies, why are they all variations not on each other but on unrelated Boeing projects (if anybody's?) The bomber is a modified XB-15, the flying boat a modified Clipper, the fighters with their pusher props are straight off Page One of a what-if fantasist's sketchbook, mimicking Northrop designs that would not appear for another five years. For example the clones of other Boeing projects echo the protruding cockpit lines and other wobbles of those planes, while the unrelated ones are sleek and smooth and what-if idealist. It's hard to believe that is just coincidence.
Third, design details don't stack up. As has been noticed elsewhere, the flying boat has no stabilising floats (unlike other near-contemporary studies such as the Westland-Hill Pterodactyl VIII or the Roxbee Cox and LP Coombes flying wing). The 30-seat airliner has a fat, stubby and hence draggy fuselage for the day, its four engines in typical what-if-meme push-pull pairs never studied by Boeing elsewhere, the two excrescences - fuselage and engines - are treated with contradictory aerodynamic priorities, the one dangling wholly below the wing in a simple and practical structural arrangement, but the other placed mid-wing in a notoriously difficult structural arrangement, there is inadequate space for passenger luggage, etc. etc. Then, a high-wing fighter in the 1930s? Aw, c'm on! Those pusher inverted-vee engines could perfectly well have been mounted higher to improve prop ground clearance - drag doesn't disappear because you dangle the cylinder banks like scrota beneath the back end - and the wing could then be mounted lower on the fuselage in the latest high-speed fashion, keeping its relation to the thrust line unchanged. And so on.
but the killer for me is the technical rationale offered for the unique trailing elevons, the suggestion that decoupling them from the wing makes things more efficient. In fact, the reverse is true. For example SF Cody, who flew the first British-made plane in 1908, tried free-pivoting ailerons located between the planes of a biplane, before abandoning them as ineffective and changing to the now-conventional inset style. What actually happens is that deflecting a conventional attached aileron modifies the air pressures over the fixed wing surface too, greatly increasing the effectiveness of the action. The detached scheme mooted here has been tried occasionally. The detached surface acts more or less like a servo tab, allowing the natural aeroelasticity of the wing to amplify its effect. Without that elasticity, the aileron is ineffectual. And the Boeing wings shown here have typical rigid-as-possible profiles, they display none of the characteristics of the necessary aeroelastic tailoring. Moreover, the supposed wind-tunnel tests claimed to have proven the scheme would have in truth demonstrated the exact opposite; that really was one embellishment too far, it kills the credibility of the story stone dead.
Sorry Zichek, forgive my scepticism, but your extraordinary backstory requires extraordinary evidence to support it, and you appear to have produced exactly none. I guess a Boeing patent or other original documents would persuade me otherwise, but not much else could.