The third quest of the death knights requires one to use some eye device of the Lich King's that give you something called (and I'm not kidding here) "sight beyond sight" (hello, did the Lich King just steal that from Liono or is now the Lion King?!?!)...

In any case, as I'm using it, WoW continues to crash for me every time... the error is:

This application has encountered a critical error:
Error #132 (0x85100084) Fatal Exception
Program: L/Program Files/Diddlycraft/Wow.exe
Exeption: 0xC0000005 (ACCESS_VIOLATION) at 001B:00806218
The instruction at "0x00806218" referenced memory at "0x00000020".
Press OK to terminate this application.
OK

And every time asks me if I want to email Blizzard (don't worry I say no each time).
Anyhow, let me know if this is fixable, it is a "training" quest and a tool I'm imaging will be necessary for future play?!?

What is the quest name?  There are a number of "Eye" related bugs for Trinity.  https://github.com/TrinityCore/TrinityCore/issues/search?q=eye  (Searching for sight beyond sight returned nothing)