I think that one reason why an organization would decide to ignore evidence from a whistleblower is that doing so admits there is a problem. For many organizations, the whistleblower is an inconvenience. While businesses and other organizations might publicly praise the idea of the whistleblower, the reality is that its presence causes disruption to the Status Quo. Whistleblowers can be silenced and in doing so, businesses and other organizations do not need to pay attention to claims that are made. On some level, this is actually happening. A recent study in the UK found that "Three out of four whistleblowers who raise concerns of wrongdoing at work with their managers have their claims ignored." Leaders of organizations find that they are able to silence the whistleblower and thus not have to address the issues that the whistleblower raises:
The findings demonstrate why speaking up in the workplace may seem futile or dangerous to many individuals. They [employers] are still shooting the messenger and overlooking crucial opportunities to address concerns quickly and effectively.
The organization that chooses to ignore the whistleblower might also find that being able to silence them is more cost effective. If a whistleblower can be blacklisted, harassed, or intimidated, it might be a more cost effective route for the organization to pursue than to actually acknowledge what is being said. Intimidation can prove to be more effective and more costly to the whistleblower than validating: "Many [whistleblowers], after being forced out of their jobs, file costly wrongful dismissal lawsuits that usually take years to resolve and often find it hard to rebuild their careers." In this, it becomes clear why an organization would choose to decide to ignore evidence and voice from the whistleblower.