A
quick check with gcmap.com arrives at a total of 17,651 mi for this itinerary. Note that Delta still uses the location of Stapleton International Airport (which gcmap has available as "DEN.OLD") for DEN even though the code moved to the new Denver International Airport years ago.
DEN.OLD-SEA: 1019 mi
SEA-CDG: 5016 mi
CDG-DXB: 3259 mi
DXB-CDG: 3259 mi
CDG-DTW: 3962 mi
DTW-DEN.OLD: 1135 mi
I think the 30% MQD calculations will round up on a per-segment basis, so you may pick up a few extra MQD that way.