Cowbobob, I agree with what you are saying, but, it may be possible to reconfigure the controller to recognise the opposite state as a "touch".
Also, the controller is shown as having a 3.3k pull-up resistor on the probe input, the LED and 1k resistor in the econo probe may be a bit low resistance for the controller input to change state correctly on a touch.
These problems are fairly easy to overcome, my scepticism, born of may years of being fed half a story, tells me to beware and check that the given schematic is really the controller for this machine.
JimB