Writing a report, in fact, is a technical skill, especially when the reporter is a Contractor who cannot "lie".
Giving this job to Lu Ping'an, in a sense, also uses his Contractor's identity to increase its credibility... Though still, not many honest people will take the contents of the report fully at face value.
"... When the members of our Special Service Team Three discovered Lei Huoren's betrayal, we were stunned. No one had any related information or speculation beforehand. His behavior was quite normal. We newcomers knew him for less than three months, but we all thought he was a capable Deputy Captain..."
First of all, is to clear any connections, this is an obvious statement, but it must be written and highlighted.