I also replicate it plugging in multicity and picking the flights that I identified as low by searching oneways, that priced out at 40k total:
DTW-LAX day 1 (low)
LAX-OGG day 3 (low)
OGG-LAX-DTW day 10 (low)
now prices at 77.5k
It also says
Outbound DTW-LAX
Return LAX-OGG
Return OGG-LAX-DTW
which is weird isn't it?
Got Avios?