CO EQS on discounted Y is 0-1, depending on fare class and booking channel.

And, no EQS for CO when flying on DL, similar to the NW restriction that you noted.

CO also only offers 50-100% EQM on discounted tix in coach, depending on booking channel, and only 50% EQM on some fares on some carriers. I don't think that trying to include all that in here makes sense, as the list of fare classes and permutations is very complex/long. But it might be worth noting.