Except he’s not really a Whistle Blower. He’s a messenger. Someone passed him the information. He had no first hand knowledge. He should be marched in front of the judiciary.
To me the issue is not whether the whistleblower is repeating hearsay. IMO, even if we were getting the story from the source, I still don't think the source is a whistleblower. He/She is a leaker who is leaking the president's private conversations.