ZOS_GinaBruno wrote: »Hey @Zakkaj! This is a known issue, and we should have a fix rolled out pretty soon. Thanks for the report!
Seroczynski wrote: »A very long thread including official word on the matter is located here.
In short, make sure the NPC is in battle when killing Balreth. Re-enter the zone if the NPC is out of combat just before the kill. That seems to be working for most (but is not 100% confirmed to be working).