Flying YXC > YVR > YCD return.

Wanted to just cut the YVR > YCD leg on the way there to hangout in Vancouver for a night or 2 and then ferry / float plane over to YCD, essentially making it an open jaw itinerary.

I know this has been asked (and answered) before (I couldn't find it with some searching) but what happens if I just don't show up for that YVR > YCD flight? Does it invalidate / cancel the return as well? Any ways around this other than a formal change?

Just trying to avoid paying $100 change fee + fare difference for simply cutting a segment of the journey out.

Thanks for any help in advance!