The switch problem might be tilting the game. Does the tilt light come on?
The capacitors on the switches do fail and cause a stuck closed symptom. If the switch is open but the test mode is showing it closed cut one end of the capacitor loose and see if it clears. There is usually a capacitor near the plumb bob tilt or roll ball tilt in the cabinet.
A limitation of the switch test is that it will only show the lowest switch number that is closed. So if a switch matrix problem is making the CPU read switches 2,10,18,26,34 as closed switch test will only tell you 2 is closed because it is the lowest switch number.