Questions about example sentences with, and the definition and usage of "Whistleblowering"

A: Whistleblowing (not whistleblowering) is specifically when someone in an organization or company comes forward to the public with information about wrongdoing in the organization. For example, a whistleblower might be someone who speaks to a news reporter about some sort of illegal activity they have witnessed in their company.

Denunciation is more broad, it simply means to criticize or condemn something. Like the president of a country might issue a denunciation of racism or violence.