Well, I'm glad you're going to look into it, because it doesn't seem to be an unusual occurrence. Security officers verge on contemptuous when people ask for service in French; they don't want to provide it. I've even taken part in protests against the Immigration and Refugee Board of Canada because a lawyer was prohibited from pleading a case in French at his client's request. People spoke out against that so many times that he was finally given the right to plead in French, although he was denied documents in French. Eventually those documents were provided. I believe the Canada Border Services Agency submitted an evidence document in English, then withdrew that document upon realizing it had to be bilingual.
This all indicates there are problems in Montreal too. We've been told the Canada Border Services Agency has been heavily criticized. I don't know if you've already heard this, but there are serious problems in Montreal.