I defeated a couple NPCs in Triple Triad the other day that I had not previously defeated. The achievement for Triple Team II did not update reflecting that I had defeated them. I beat Ourdilic and Joellaut in Coerthas and the counter did not move that I saw. I also beat the Indolent Imperial in Mor Dhona that night, but had not looked at the counter before, so unsure if that one also did not count.