Please provide a step-by-step process of how the bug can be reproduced. The more details you provide us with the easier it will be for us to find and fix the bug:
In which language do your server is set ?
(Is it a GPortal one ? :P)
Oh, EDIT didn’t read it was on official so yes it is probably set in German as this is the default setting for GPortal servers.
In my experience I found that the thrall / ennemies names and some IG messages are displayed in the server language and not in the language you selected in your client.
(Yes I laughed too the day I saw German unspeakable follower name instead of French )
On my server everything alive is in English as it’s supposed to be but as soon as you kill a NPC its name turns to German (which is not wanted because it’s a bit confusing).