But was it such a good idea to Evacuate 160+ people in the dark from an aircraft that was not on fire ?
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Did the Crew initiate the evacuation, or did a passenger panic when they saw flames coming from the Other Aircraft, and someone opened an Emergency Exit, everyone else followed ?
The ATC recording in post #17 makes it pretty clear that the Westjet crew (at least initially) believed that their aircraft was on fire, and that they initiated the evacuation.
The cold temperature notwithstanding, I can't think of a better place to initiate an evacuation than right next to the terminal, with plenty of marshaling staff nearby to shepherd passengers to safety. The crew made the right call.