Well if the NW# is on both BPs it might be SoL for both to CO and no way DL after 10/24 on the way back.

The question is what CO will do regarding the return since there was no way to get miles with DL after 10/24, they might give the OP credit to their CO acct for the return, but unless their CO# is on the BP for the OutBound flights, I dont see CO giving in on them

If theres no FFB# on the BPs then its a toss up with the OutBound, maybe if DL KOs them and sends a letter that that is what they did, CO might credit it. But I wouldnt place a bet on getting the CO miles on the OutBound