I'll go through the steps I took below and I invite anyone to follow the same steps and identify anything I've done that isn't accurate based on known data...
1. We know exactly when the Cargo Law photo was taken, and where the camera is located and the direction it was pointed when it took the photo.
2. We know exactly where UPS902 at each minute based on the data from Flightaware. Flightaware UPS902
3. It is possible to plot the lat/long of UPS902 at when the Cargo Law camera took its photo. 
4. Plotting the line of sight from the Cargo Law camera at the time of the Cargo Law contrail photo was taken crosses the flightpath of UPS902 at almost exactly the lat/long of the aircraft for that time as recorded on Flightaware.See this post
Therefore, it is safe and logical to conclude that the Cargo Law camera took a photo of the UPS902 contrail.
Now, lets take a look at the Leyvas video, and specifically a still from the video that shows Long Beach harbor.
We don't know the exact time the video was taken, but we do know it was sometime around 5:15. Plotting a line of site from the helicopter toward the contrail in his video provides the following (The red line of site is from the Leyvas helicopter and the yellow is from the Cargo Law camera).
Not surprisingly, the line of site from the Cargo Law camera toward UPS902, and the line of site from the Leyvas video intersect at very nearly the same point. Therefore, it is safe and logical to conclude that the contrail in the Leyvas video is the same contrail photographed by the Cargo Law camera. And since we already know the Cargo Law camera photographed UPS902, we now also know Leyvas did too.