I don't have the time to figure out the physics, but a body falling from, say, the 110th floor through the dead drop would be hamburger as soon as the chute began to curve. You apparently missed the part about the "drop bags", which would "catch" on the confined air in the tube as you fell, acting like a parachute, limiting the speed of descent even in the vertical sections, and simultaneously protecting your skin from scraping on the walls of the tube.
Why not a real parachute? There is a company that is headquartered in the Sears building in Chicago that makes these special building parachutes that you connect to a bar so it deploys immediately. I saw this on CNN shortly after 9/11 and quite a few companies in the tower were ordering enough for all of their employees to use.
I didn't miss that part, I read it very clearly:
"...the chute bag".... This is a canvas bag which you jump into and ride down the chute.
...It is sewn, as in the diagram, so that the air pressure from falling inflates the sack causing it to seal the sides of the chute
You are not serious that you think a canvas bag is going to create a seal in the chute that will slow a body's decent as it approaches terminal velocity.
I'll say it again: hamburger.