I think I read Clapper or Brennan sent Comey. I can’t remember where or when I read that.
I read it was Clapper. He was working at CNN and they needed a reason to report on the dossier, they needed an “event” that included the dossier. By having Comey brief the President, Clapper was able to immediately notify CNN of the event and that’s when they reported the story to the public.