Hmm, where in my post did I say anything about airports or airfields? You will probably have to clear all the air traffic along the reentry path of a non-schedule Dreamchaser landing.
Disruption to air traffic will depend on where and when the landing occurs.
You really can not have an un-powered reentry glider mixing with any air traffic.
Sorry, I misunderstood you when you used the plural "landing sites."
Obviously, but this is true of airspace in general. Whether it's a lifting body, capsule, rocket stage, falling satellite, etc. Air Traffic Control will do their best to keep two airborne objects from occupying the same airspace at the same time.