A:Answer I'm answering my own question.
This device comes with firmware 105, which does not display temperature even you ask google assistant. You need to upgrade the firmware to the latest
system firmware version:306
cast firmware version: 1.28.101871
Took me a while to figure this out, I've reset my device million times and it finally upgraded to the latest firmware. Press and hold the mic button for about 12 seconds until you see solid orange light. During the setup, if it shows "LOAD", that means it's updating the firmware, do not continue on your google home app until that's done.