[Quickurt]

You can check both of those switches with an ohm meter. They should both be normally closed switches, i.e. when the clutch pedal is in full up position, disconnected switch should read zero, or very low ohms, (2 to 5 ohms) and open line when pedal is depressed. Same for brake. If brake reads open line when in up position, you are on brake light circuit. If both on brake pedal switch read open line when the pedal is up, there's your culprit. If the clutch pedal switch reads open line when the pedal is up, it's your culprit.
Jiggle both repeatedly while testing, as this is an intermittent problem. Very hard to find. You'll have to duplicate the problem while you are testing. If the switch loses connection for just an instant, bam, the cruise shuts down.