The intelligence did not come solely from Canada. Some was provided by an unnamed ally in the Five Eyes intelligence alliance.
That's the big point in this story for me. When you have another of the five eyes (Australia, Canada, New Zealand, the UK and USA) corroborating the information it makes it all the more damning.
Remember the best way we can spy on ourselves is by asking another 5eyes what they spied on inside our borders. They have the resources, and we're not in trouble for internal surveillance when we use those resources.
In addition to restrictions on sharing intelligence from Five Eyes allies beyond the group, let alone publicly, there are also issues with the admissibility of evidence in courts that is gathered under intelligence legal exceptions.
Ensuring that the judicial court process isn’t marred by inappropriate release of intelligence would seem to be a significant challenge in this case.