The War Measures Act [0] is a law that grants government powers in times of war or insurrection. There was, you guess it, an insurrection in the 70s [1] and the it was appropriately triggered.
Also the whole article describes an operation that even senior military commanders were unaware of — what possible connection could there be to the PM?
Pure dumb speculation.
[0] https://en.wikipedia.org/wiki/War_Measures_Act [1] https://en.wikipedia.org/wiki/October_Crisis