All the coefficients of known probes are already built into the webui, so we don't have values for TP-08. If the company will provide the datasheet for the thermistor used, then I can calculate them for you (using curve fitting). It can also be done by mating one up physically with a known probe and sweeping it through your desired temperature range and HeaterMeter can fit a new set of coefficients although it has to be done through the SSH Interface.
A bit of searching suggests that the ThermoPro probes and the iGrill 2/3 probes are the same. The HM has presets for the iGrill 1 and I don't know if anyone has tested them with the iGrill 2 or 3.
For a quick test, select the iGrill probe preset on the HM and see how close they are in a bowl of ice water and at boiling temp.