You can't find Zero in the list because they didn't register with either RIV or Transport Canada that their USA Domestic Market motorcycles meet Canadian standards (they likely do, but they didn't register it). The Canadian Domestic Market motorcycles do, which is why they are sold at Canadian dealerships.
I have no idea how/why some bikes get on to the list and some don't; I think that sometimes it's a way to protect Canadian dealerships. There's a 4-page thread about attempting to import a KTM from the USA to Canada:
http://www.advrider.com/forums/showthread.php?t=365269. You can try to get letters from the manufacturer stating that the vehicle meets Canadian Transport Canada standards, that it doesn't have any recalls etc but since the bike isn't on the RIV list that might not work either. You can pay extra money to an importer i.e.
http://www.miac.com/ to try and get the vehicle in, as noted in the advrider thread.
I don't know if you're buying NOS 2011, or a new 2012. FWIW the 2012 MSRP's are at par for Canada/US, unless you're getting a great deal it might not be worth the effort (and potential headaches involved).