I think there's a lot of digital evidence from that early morning that has not been released, with good reason. For instance, in the PCA, they include a map of the white elantra's movements presumably leaving Pullman before the murders, and then coming back afterwards. But really, the elantra is only shown driving on campus beforehand, not actually exiting town. The next we hear of an elantra is 33 min later on the southeast side of Moscow (Indian Hills Dr). That elantra's movements can be tracked by camera footage and timing, finally leaving the King Rd area via Walenta Dr just after 4:20. Jump ahead an hour and an elantra is on Johnson Rd. in Pullman, seen on 5 cameras heading back through town and campus. The only thing linking the two elantras as being one in the same is possibly no front license plate.
There's no footage included in the PCA that shows the white elantra specifically leaving Pullman, and there's nothing at all showing a white elantra entering or exiting Moscow. Phone pings later support that BK's phone had the same route as the elantra in Pullman both before and after, and it puts his phone south by Genesee and back towards Pullman, but there's a big gap in phone data around Moscow. Per the PCA, his phone isn't placed in Moscow, his phone/elantra isn't placed leaving Pullman, entering Moscow, or leaving Moscow. Assumptions have to be made that these elantras are the same car, which again, is based only on what we see in the PCA.
IMO, there's more camera evidence than what we see in the PCA. It wasn't needed in the PCA, because of the DNA evidence, but extra camera evidence will support BK as the killer during trial. JMO. If they don't have any other footage, then the D will definitely want to get the DNA evidence suppressed, because the camera and phone footage could be lacking. JMO.