No matter what, ICN is very good about disability services and has priority lanes and special help for that stuff everywhere (not like say America where it's just dismal). Contact both Asiana and Air Canada about requesting extra mobility services - as AC might say "oh we don't do that, talk to Asiana" or vice versa.

https://www.airport.kr/ap_lp/en/svc/...tra/servtra.do

And also Asiana boards just 30 mins before departure, so you'll be fine. And can use business lane as low mobility passenger for assistance etc.