ORIGINAL: dirtybird

You need to perform more tests to determine that 2.4 was actually interfered with. Remove the servo connections and monitor the servo outputs with an oscilloscope. I see you are in AZ. If you don't have an oscilloscope meet me somewhere and we can use mine.
I strongly suspect the interference was coupled directly into the servo leads and interfered with the drive pulse.
Another way to test it but not as good is to remove the servo from the receiver and drive it from a servo tester. If you still have the problem you will know it is not coming from the receiver. This is not a sure test though because you don't have a full system and the output impedance of the servo tester will be different from the receiver.