Satellite and Signal Reality Check

Satellite claims are useful because they leave public, practical traces: visible passes, radio signals, tracking predictions, customer services, weather imagery, timing systems, and amateur reports. 
 Try a Visible Pass 
 Use a satellite-pass prediction site such as Heavens-Above. Enter your location, choose a visible satellite or the ISS, and write down the predicted direction, time, brightness, and path. Then go outside and check. 
 Try Amateur Radio Evidence 
 Amateur radio operators track and use satellites with public pass predictions and open reports. AMSAT status pages show reports from operators around the world. This is valuable because it is not one agency publishing a picture; it is many hobbyists reporting practical signal behavior. 
 What a Flat Model Must Explain 
 
 Why passes occur only at predicted times and directions for specific locations. 
 Why Doppler shift changes during a pass. 
 Why different observers see different pass geometries. 
 Why radio links begin and end as if a moving object passes over the horizon. 
 Why commercial services, amateur reports, and orbital predictions agree. 
 
 Claim Lab Question 
 If satellites are fake or balloon-like, what should happen to pass timing, signal strength, Doppler shift, and visibility as observers move to different locations?