-20C is not cold for a dog like Snowflake.
An expert would know that it would depend on the amount of the exposure and the weather conditions (wet vs dry). The breed of Cruz's dog - a small poodle - was not bred to live in such temperatures. Nor has that dog been acclimated to such temperatures living in Texas. So, the claim that -20C is not cold for Snowflake is pretty fucking stupid.
However, Snowflake was left in the house where the temperature was not -20C with a security guard checking in to let the dog out a couple of times a day and to feed the dog once a day and to give it water once a day. That suggest to me that the Cruzs have no real friends they can count on to ask to care for a dog.