hey there
Just looked at your email, the guy who had the letter, never replied but I did use this as leverage on GM Canada. The total bill for the repairs were in the
3 to 4 thousand $ range, I was able to use what I learned here to get the dealership to convince GM to eat all but $500 of the costs.

Got to say the dealership was very helpful so that would be where I would start and mention about the canyon recall for the same engine and push for good will program.

Keep us advised
Best of luck