Grand jury testimony shows the woman who drove suspect Eric R, Holder away from the March 31 shooting had gone to the station because her car and license plate were on the news.
Testimony shows a front desk officer turned the woman away.
The Los Angeles Police Department says the matter is under investigation.
A grand jury on May 9 returned an indictment charging Holder, 29, with murder, attempted murder and other felonies. He has pleaded not guilty.
The woman testified that Holder was a friend she had known for about a month and that she believed the two were just stopping at a shopping center for food.
She saw Hussle standing outside his South Los Angeles clothing store, The Marathon, expressed her excitement and took a picture with him after overhearing Holder and Hussle's conversation about "snitching."
The woman and Holder had pulled out of the shopping center and into a nearby gas station when Holder loaded a gun, told her he would be back and walked back to the shopping center, the woman testified.
She said she heard two gunshots, and Holder returned moments later telling her to drive. She said she didn't learn Hussle had been shot until later that night.
RELATED: Nipsey Hussle shooting: Rapper told suspect of 'snitching' rumors, court papers say
Witnesses heard Holder and Hussle, both of whom have ties to the Rollin' 60s street gang, discussing "snitching" minutes before Hussle was shot, according to the transcripts.
The Associated Press contributed to this report.