Genie Babcock is like any other typical police officer, who takes her job serious enough, especially when going by the book.
Genie was seen responding to the 211 in progress at the bank that was being held up. There, she sees Riggs going into the bank with some pizza to distract the robbers. Just then, she was listening to Riggs on the speaker from the van having those robbers finish him off, or so she thought.
Upon hearing the shots fired, they were waiting on orders to go in. Just then, Riggs and everyone else who were held hostage at the bank were evacuating just in time before the explosion.