The term, hostile work environment, has a very specific meaning in employment law. What you have described may be very unpleasant but it is not an HWE in the legal sense.

It is fairly common for someone who is angry to make the statement, "I could kill you/he/she/it" but it rarely means more than just an expression of anger. Very, very few people who make that statement actually kill anyone. So why in this case are you feeling that your life is in danger?

Beyond that I, like AJ, would like to know what it is that you want to have happen next.