Missing Quest NPC

Since the expansion release I've had issues where I'll accept a quest, but the quest will be in another language in the Journal. Japanese was most common and more recently, French.
I'll be able to speed through the dialogue, but the dialogue boxes are blank.

This happened with the level 57 quest, "An Engineering Enterprise." Quest and details were in French, no visable dialogue. When I went to turn the quest in to Tataru, it acted as though the quest wasn't turned in at all. She still had the turn in icon over her head.

I logged out, trying to reset it. When I was back in she was gone altogether, however the icon on the mini-map that there was a quest was still there.

I ran the reset through the launcher, no change.

Logged in from my brother's computer and I was able to get the quest. When I logged back in on my computer the quest was in my log, but my duty list would not display and the quest info was erroneous.

Logged in again from my brothers computer, completed that quest and I'm now ready to pick up, "Lost in the Lifestream" and I'm back to not being able to see the quest NPC.

I had this problem as well. The only workaround i could find was changing your language at the game launcher to japanese, for some reason that made the quest npcs reappear. I'm finding the problem becoming more frequent in more story quests as i progress. Very frustrating having to log out and change the language all the time.

I've also noticed that a lot of sidequests have Japanese titles, Azys La being the worst place were every sidequest has japanese titles