The temperature wire in the 4pin connector is the thermistor output, NEJE would like you to buy their plug in control/display unit, however, they do publish the external circuit needed and the resultant output voltages, you would need to parse this data and make a suitable display if you wanted to DiY it…easier to give Neje the asking price!
Your air assist will do little to clear debris from the cut I fear, you will need a more directed air flow into the cut, something like this perhaps
