If you're using a 4+ channel transmitter/receiver with two joysticks, there's no reason to use a 'switch' method. You can set up one stick to control the rover and one stick to control the pan/tilt.
Doesn't even have to require any code modification either. Just connect the pan and tilt servos directly to the appropriate channels on the receiver. Voila, you have pan/tilt and rover control without any switching required.