I have been unable to test with the PG9905 however, you may be able to create a notification based off the thermometer hitting the high or low threshold, this appears to be confirmed by another user here.
The high and low temperature thresholds can be set anywhere in between 180 and -40 degrees in sensor programming so long as the panel is on firmware 2.4.
Another approach seems to be using a ADC-S2000-T-RA remote temperature
You can create a temperature alert using the RTS through Alarm.com. The alert can be set for a High of 105° F and a low of -20° F
However, you would not want to mount it in the freezer either as its operating range is 32° to 90°F (0°C to 35°C)
Since it is a Z-Wave device, you would be beholden to having a strong mesh network in the area as well.