This is my take on your problem; the RF noise is not creating interference at 2.4 GHZ and then causing the servos to move. If you had interference at 2.4 and it interfered with the radio it might cause some data packets to get corrupted but it would not cause corruption of the packets in such a way as to cause the receiver to move the servo, packets have checksums etc.. The receiver would just throw away the corrupt packets and wait for good ones. If all packets were getting corrupted then the servos would just sit there or the radio would detect no good packets and go into failsafe.All that said it’s likely the RF interference is being picked up on the wires going to and from the servos, if the interference couples into the ground power or signal wires it can cause the servos to nuts. Make sure these wires are kept away from RF sources etc. these wires are not immune to RF interference!