We tried something similar:
My youngest had a medical emergency that we were at a hospital at 12:00 (our flight was CPH-PVG at around 18ish), we were absolutely convinced that he was fine (he was seen by 8 doctors and 4 said he was fine and he wasn't) from the symptoms and how he behaves and reacts.
We decided to go as our friends were expecting us and we really want to be there instead of home. So we pushed OLCI until 15:00 - make sure SK knows that we are coming. The hospital released my boy after giving him IV antibiotics (I had to run to the pharmacy to pick up another 2 big bottles) at around 16:00. Then I drove to pick up another 2 kids who were waiting at the school, we got to CPH and bag drop around 1 hour before departure (*A so very little queue). They didn't comment on us being late or anything like that.
My kid was totally fine during the flight and he was fine the whole time - he wasn't in pain and all the blood test showed nothing - that's why we decided to go.