"certification" usually refers to the Ontario safety check. That would not include a check of the oil. I THINK a car can even pass "safety" if it is not running.

I would try to get the mitsu dealer to give you a letter IN WRITING saying that the chain failed due to poor mainenance, and that they are convinced that the oil had not been changed in a very long time. Then take THAT letter back to the dealer that sold you the car and claimed the oil had just been changed, see if he will do anything for you.

I am guessing you are going to have to take him to small claims court.

I think there is some sort of "governing body" for used car dealers...maybe they can help?