I don't see conflicting info with this website: https://www.torontopearson.com/en/co...estination=bog

(i selected an airline/origin/destination combo that was similar to yours)

TechnoTourist linked you the AC documentation for US to International connections at YYZ, and you linked at the AC doc for International to International. At YYZ, all US-originating passengers follow the same procedures as an international arrival for the purpose of entering Canada or connecting onward. One difference between the two web pages is that one of them doesn't tell you where your baggage is going, but rest assured your back will still go to Seoul because you're directed to go to the Connections facility rather than baggage claim where you'd need to enter Canada, pick up any bags that needed a re-check, and do just that.

Of course, on the day, if the check-in counter tells you otherwise ("please pick up your bag in Toronto") because of an extraordinary deference in usual operations ("you'll have to overnight in Toronto due to a delay"), listen to them, but that'll be very unlikely.

The two AC docs (and the Pearson doc I linked) are functionally saying the same thing