A couple of things.
First, I don’t think Canadians would take too kindly to be referred to as “Americans.” They’re happy to be called “North Americans,” but they bristle when they’re confused with their neighbors to the south. (Occasionally you’ll hear a Canadian say, “I’m an American too,” but that’s an expression of objection to the USA’s appropriation of the name, not a statement of solidarity.)
Second, Americans have no objection to acknowledging that many English words come from Spanish, especially “cowboy” terms like chaps and rodeo, which are widely hailed as coming from Spanish. You’re ascribing a distaste for Spanish etymologies to Americans that does not exist. What we do have a distaste for are unfounded Spanish etymologies.
Third, speculation is fine, but in many of these instances you’re bringing up the words where the origin is quite well established. And generally we don’t look kindly on speculation without at least some research. (Questions are one thing; stating speculation as if it were fact is quite another.)
As far as I know, there were no Spanish explorers in Quebec, the area that was first known as Canada. The word is first recorded by a European in 1535, when Jacques Cartier noted that as he approached the Ȋle d’Anticosti in the Gulf of St. Lawrence his native guides pointed out the “chemin de Canada” (route to the town). Cartier also noted that kanata was the Iroquis word for “town.” The specific town in question was a native village on the site of what is now Quebec City. But later mapmakers using Cartier’s notes erred and labeled the region Canada. Over time, the name came to encompass the entire country, from Newfoundland to British Columbia.