I accidentally logged a walk as a run and have managed to change it to a run on the Garmin app, but not on my watch after I synced it. Trying to do this so it will count my run on the Nike running app as well.
I do not think that Nike cares about (or can find out) what is on your watch. They connect to the Garmin Connect account, so if it is all right there, it is all you need