Interesting way of framing it. But, I don't think that's the way this is going to play out. Trump has quickly isolated himself on the trade front. He's leaning too far out in front of his skies, and is going to do a header...unless he pulls back. I think blowing smoke up Trump's ass is always a good strategy, one that sort of makes me gag....But, if Carney can end the tariff nonsense this way, then so be it. I think Carney could work with anyone who was reasonable....And Trump can, on occasion, be reasonable....
But, the reality here is that Trump NEEDS to save face. His great tariff experiment hasn't really hit the average American. Yet. But, he's already painting a picture of more expensive goods and empty shelves. How will people outside his cult react to that? What can he do to walkback the bullshit with China and the rest of the world. He likely is lying about the number of countries begging to make a deal (I'm sure some have tried, but I doubt its over 15), so we'll need to see what happens down the road.
All that being said, I'm not sure how much Carney wants to deal with China, so this could work out as you say. Canada and the US have been good neighbours for over a century. Trump has poisoned that well...and, that basically means he either fixes shit, or we aggressively look to other markets like Europe or Asia. I'm sure there is demand for oil and natural gas...or wood and rare earth minerals.