Visible crew/equipment: When Neil (De Niro) breaks into Van Zant's apartment and shoots him, watch as Van Zandt flies backward. You can see a wire running up through the bottom of his sweat pants.
Visible crew/equipment: In the drive-in shootout scene, the camera and crew are visible in the rear view mirror in the cab of the white Dodge pickup fleeing De Niro and Kilmer.
Visible crew/equipment: When Neil is sneaking up at Van Zant's house, you can see both Neil's and the camera man's reflection in the glass windows on the house.
Visible crew/equipment: When Vincent Hanna decides Neil is already gone, he heads to his hotel room. He enters the room and walks out onto the balcony. The shot of him approaching the balcony and opening the sliding door is shown from outside, on the balcony itself, and the cameraman (wearing a white shirt) and camera are visible reflected on the left side of the sliding glass door. It is more evident as the shot progresses, because the cameraman shifts position and the reflection moves further to the left, becoming larger. (02:21:54)
Visible crew/equipment: In the scene where Hanna and Casals break into Hugh Benny's apartment, when they break down the door it can be seen that a stuntman is filling in for Pacino.
Visible crew/equipment: When Michael Cheritto comes out from the bank just before the shootout scene and gets on the car, a cameraman and a crew member on his right side opening the car door are reflected on the windows.
Answer: Waingro helped Van Zandt track down Trejo. Waingro then tortured Trejo and threatened his family if he didn't give up McCauley. With his back to the wall, Trejo gave Waingro and Hugh Benny the details of the bank heist, but Waingro killed Trejo's family anyway and beat Trejo almost to death. Benny then gives the tip to the police on Van Zandt's order.
BaconIsMyBFF
I wonder how Trejo was tracked, I don't remember his name being revealed during Waingro's time with the crew, or any other information.
Well, we never see the crew prior to their first heist. Trejo could have given Waingro his name during the planning of that heist.
BaconIsMyBFF
Waingro met this crew only once. How would he know who Trejo is or where he lives? Right before the heist, Trejo is asked to mislead police away from the heist.