Actually every single report about this story has noted the cars would have failed the emissions test without the software specially designed to cheat and pass (if not there would be no reason to have said software!).
I was speaking in terms of Canadian testing. Turns out, I was still wrong - I assumed Canada was strictly performing tailpipe tests, not ODB instrument testing. Turns out they don't do tailpipe tests on cars newer than 1998 (this is news to me), meaning the defeat device is the exact reason why I hadn't heard about any cases of cars failing the emissions test.