L.A. Noire Homocide Desk case help?

I just completed The White Shoe Slaying case and I was reading some guides and they mention an interrogation of James Jessop right after you find the Yellow Cab 3591. I found the cab, but it didn't tell me to go back to Central Police Station, and when I did by myself, Jessop wasn't there. The guides also mention the Bus Depot. Once again I wasn't directed to go there, I just went to the Hobo Camp. I still completed the case with five stars, charging the hobo, Stuart Ackerman, with the murder, but I just want to know why I missed those two sections. I'm playing on PS3 if that changes anything.