Whistleblowing is about wider issues involving BCG. It is different from a grievance or complaint in that they are not about personal concerns. Whistleblowing is the act of disclosing about wrongdoing by BCG.
A whistleblowing concern is if you see BCG doing something illegal, being involved in financial wrongdoings like committing fraud or putting the health and safety of groups or individuals at risk, either members of the public or contracted workers.