Sorry, I may be incredibly thick, but what "omission" do you refer to in the NWT ? or are you saying that in the Mags. etc the Org. should claim the 144,000 are all Mini Mels ?
The problem with doing that is they will be laughed at by all non J.W's who have an interest in Scripture, but as that has never stopped them, in all their history, from spouting total nonsense and adding to Scripture in a blatant manner with zero shame, you are probably right, they ARE missing a trick.
But perhaps they may not wish even more to be "partakers" claiming to be of the 144,000, a figure already proven to be ridiculous.