In the Fighter's guild quest "Alit Trouble in Menaan", there's supposed to be a pack of Alits in the mushroom grove to the west of the town. These Alits did not spawn at all, causing Darra to not properly guide you to the correct area.
Currently Darra will walk 5 feet before asking you how are you going to kill these non-existant Alits and then sit there.
The "local area" topic in Menaan mentions the "Inuibbisa" tribe. I've looked in the CS and found no other mention of this name, save for that one topic. I wonder if it's a leftover from Rats' ambitious NPCing which never got quite finished? Anyhow, it should be removed. Screenshot below:
Just southwest of Arvud, first time in this area. I haven't met this NPC or Olman Uvayn or talked about him with any other NPC, I saw the dialogue option and clicked it and got this which looks like something from halfway through a quest I have not started. I believe an ashlander camp a couple cells west of here was marked on my map as I did this.
I have decided to compile a running list of all the bizarrely dialogue free NPC's I find in DoD/EoE. Some of these may be involved in quests, but even so in vanilla you can generally still ask for generic rumors or trade info...
Mortenius Becca, no dialogue (made fix)
Garila Delvarrapal, no dialogue (made fix)
Senar, only one generic topic
Duchess Perulia Jandacia, doesn't have much to say but is probably a To Be Written case