Oh man when I first saw Nhaza'a Jaab my mind was spinning with potential theories trying to place them into the Ul'dah puzzles. So Ebon Claw is 1 of 5 deadly sell swords and his blade is eerily similar to one I've been trying to place FOREVER...for more in-depth see Anonymoose and my own posts. I know it's a huge reach and I always try to find out this question but it's explained that they are indeed involved in assassinations, sure the blade might just be a common one of Ul'dah but in a way I also feel SE wants this theory to be made when Nhaza'a shows it off, sure a lot of boasting tends to be the person sticking their blade out at an enemy but this is a special kind of baddy and they tend to have special weapons. I'm not saying Nhaza'a himself was the assassin as he's clearly right hand and the assassin was left handed, just that the blade and the throwing blades match up with the screenshots.

Niellefresne, Lord Lolorito, and Memeriga all share one common goal...a form of Necromancy. Nielle wanted to revive Warburton and ask him what the threat was. Lolorito wished to obtain an item through the Alacran from the Sultana that was similar to the Necromancy used by the Sil'dih which of course led to their own demise. Memeriga also wanted to use Necromancy to obtain an army similar to Lolorito but he messed with the wrong folks. Like I said a bit of a reach but hey the question of "Who assassinated Niellefresne and why?" hasn't been answered so I take what's given. (Though I do like the theory that Thancred was the one in 1.0 and would have been given a similar "betrayal" story by Tanaka that he was given by Yoshi P in 2.0 course thats just delicious drama for the Thancred fanboys and girls~).

Now all that aside I have to bring up a question about the 1569-II that was damaged by Garleans. I assume the number refers to the date of manufacturing..but in 1569 the Garleans weren't active in Eorzea yet, they were still hanging out in Ala Mhigo it wasn't till 1571 that the VIIth under Gaius van Darnus began it's march into Eorzea beginning their propaganda about Eikons and such.