Originally Posted by Bucking Bar

Smarter move would be to ID90, or whatever reciprocal travel arrangement your airline has ... or drive across the bridge from Detroit.

There are certain international taxes which have to be collected which require a "tax ticket" (I forgot what the exact term is called) and the Agents wont work you with out it. (having learned my lessons trying to get out of Canada with lap child which generates the same issue ... I put a gate check bag tag on her toe ... the Canadians were not amused ...)

If your airline has a JS coordinator, call them. This is their area of expertise. If you don't have a JS Coordinator, then talk to one of your own Gate Agents, or call the other airline's JS coordinator. When I do that sort of thing I try to find the most experienced Agent I can find and buy them a cup of their preferred beverage ... it is a bit of a PITA to generate the "tax ticket."

I don't even try to international JS on my own carrier.