Your lists are so thorough it took me a good while before I found something you don't have1
Dread Wastes: Sharpshell Wader (dragon turtle model). Every one I saw (in a few different spots) was level 88 and had the green shell/grey body that is
RidingDragonTurtleBlack. The only ones I found were in deep rift areas between Dread Wastes and Townlong Steppes. Couple of shots attached.
- WoWScrnShot_041512_124546.jpeg (669.79 KiB) Viewed 3397 times
- WoWScrnShot_041512_122453.jpeg (470.37 KiB) Viewed 3397 times
The colours look very different in the two shots but it must be due to differences in lighting. There's no other colour they could be.
Oh and as an aside, I also saw the new mantid tank model along the same valley, further west (pic attached). It was a named one and was classed as a humanoid so it's not a good first sign that they might become beasts. Ah well, not like we were expecting them to be.
- WoWScrnShot_041512_120937.jpeg (647.32 KiB) Viewed 3397 times