I'm going to ask an african american colleague to read passages including the n-word in my place
Have you had to read the book before?
Ha! Many times, I can't remember how many
It can be difficult to read material that you are not comfortable with and it is okay to find other methods to get others to hear an important text.  You seem to cheerful to have them say such a hate filled word.
I have never asked them to read the book before and I was always offended when I had to. I know the passage by heart anyway.
Don't force them to read things if you know you will make it awkward. If you do this they can report you to HR and you will lose your job for being inappropriate.