The sticky on VS codeshares currently implies that EQMs will be given for all VS flights between a set of US cities and LHR. In fact, it seems that there are newer VS flights that have been added that do not (yet?) have a CO codeshare, and thus would not be eligible for EQMs. It might be worth suggesting that you need to check the CO timetables to be sure that a flight is listed before assuming it is a codeshare.