I don't think this computer was designed to offer real time temperature measurement with NIST traceable accuracy, nor do I think that anyone else offers that level of temperature measurement performance either.
Indeed! If you want that, get a Sensus Ultra or something similar.
Temperature measurements on PDCs are a secondary feature. That's true on ALL dive computers. It's not a necessary element of it's primary function ... time, depth, and real-time decompression calculation. It's important to always keep that in mind.