I see a slight misunderstanding here, Spaz. I think your statement
I read they have test equipment to measure the RCS on ship after repair.
is what's caused the problem. The RVR, you're talking about, doesn't measure RCS. RCS is a property of the entire airframe. The RVR is a bit like M2's flashlight option (kind off), which simply looks at the properties of the repaired area and allows the user to compare it with the spec to see if the repair has changed the stealth material's properties beyond defined tollerances.
If you want to measure RCS you need to put the aircraft on a pole and examine it with radar energy appropriate to your chosen threats.
Hope that helps.
Courtney