I am sorry to hear about your troubles with Mr. Slusser!  I know him from high school (one year).  I see he has not worked out some personal issues and is making a fool of himself in public.  I feel very embarrassed and ashamed.  He isolates himself from counsel and social conformity.  I warned him to finish school and not just get into carpet cleaning, but he is an underachiever.  I hope you will take this into account.  He was abused and misunderstood as a younger person, never talked about it and so forth.  I will pray for him.  Please accept my apologies for my wild brother.  I hope one day he will conform to socially graceful behavior.  I think he is calling people because he wants to talk!  As weird as it is.  Perhaps we should respond with inquiry as a cognitive tool, rather than mere anger - as he is misguided.   Thankyou.  Yes, that speech is inappropriate and shocking, outrageous.
As far as dangerous goes, could be!  Substance abuse is a big factor here!  Social Security and then some!
Cheers.