There were many aspects of a real mission that could not be simulated in a Moscow suburb, of course - such as weightlessness and the dangers associated with space radiation.
Presumably, the USAF thinks that "the right thing" would involve pulling LightSquared's license, but for its part, the company says it believes Shelton is referring to a test conducted by Garmin (possibly explaining that recent outage in the Southeastern US?) using simulated interference filters -- not the actual filters that it has spent several million dollars developing and perfecting.
As you note in your email, our use of a Figure 4 would not preclude a more detailed and thorough comparison of simulated and observed amplification in some later publication.