The government has all of the credit card service fees listed on a web site, and according to them all of the MNBA cards have a 2.5% service charge on foreign transactions. (See "spoiler" below.) And the XE.com rate for today is 96.7. You sure they didn't gross-up the amount billed to your credit card by 2.5% before applying the exchange rate?
http://www.fcac-acfc.gc.ca/iTools-iO....aspx?lang=eng