I have filed a defamation of character against a supervisor at work. Not my supervisor. I wrote a letter to HR on the allegations and met with them twice. I have witness names on my report to prove that this has happened. HR said they would investigate this. Today I got an email from the supervisors boss asking me to write down everything that went on that afternoon, times and so on. Why do I have to answer to them when it should be them who are investigated. Nobody has talked to my witnesses. Could I ask for, in writing what my witnesses have to say? I feel like they are trying to set me up and I do not feel that i need to respond. Please advise.