Alcohol and ketamine is a known bad bad combination. 500mg is a damn lot of ketamine and morally there is no difference than drugging someone against their will by non medical people for no medical purpose.
I don't like the moral policing of any group. But there is always a choice to politely say no and go on with your live. Everyone has there own values.
I don't agree on the moral witch hunt that followed either. Take his private email, reframe it in the media. It destroys a person and I think that is very wrong.