if you have decided to come back with your original country's passport, then I suggest you that do not show your Canada citizen card to the airplane company when you check in, maybe do not even let them know. One of my friend's friend, was in a similar situation as you are now. So he bought the ticket, and then show his citizen card during check in. (we're from a visa exempt country but the workers will still ask some questions, to be sure the passenger will not have big issue when they arrive Canada). Later, the airplane company refused the friend to board because "they have got the official announcement from Canada that airplane companies should be sure that all passengers have eligible documents to entry Canada before offering the boarding pass, otherwise, the company will be punished. Under the list, it shows that Canadian cannot go back by citizen card." So, that friend was unable to board, and he called the embassy because he "thought" that rule is not right. He even wrote complain mail to CBSA but the only answer was "apply the passport."
I personally suggest you to apply passport, instead of having so many headaches. Sorry about my writing, hope it will not confuse you, good luck.