vdtol,

I, a PE member, just checked availability for the specific dates you mentioned for your trip for a party of three to YVR from GRR and found them available for 112,500 miles, PerkSaver outbound via DTW and PerkPass (formerly known as RuleBuster) inbound via MSP. When I checked from DTW for the same dates, I found them for 75,000 for nonstop outbound and via MSP on inbound.
So if you are not a PE member, that doesn't do you much good except to hope that the seats will not all sell out and allow you to get these seats later. If the seats were selling well, I don't think I would have been able to get these at PerkSaver rates, either.
Good luck.

HJ