Maybe SLouTH, or some kind of digital evidence??
One day we'll find out !
I bet they have digital evidence (dashcam, gopro etc) plus an informer.
The informer provided the digital evidence which allowed the police to watch the crime and understand it as a deliberate attack.
The digital evidence may have uploaded to a site or device that the informer could view.
I wonder if Sam was deliberately chased and mowed down by the car and it was digitally captured by phone, watch, and dashcam etc
Captured the crime, the heart rate, the shared location, and maybe some audio.
I wonder if the body is hidden in the local area not far from town or his home. I think the likelihood of it being in water is very high.
I think the phone was tossed suddenly.
I wonder if it was forgotten and its disposal was a (panicked) hasty afterthought when it was sighted still sitting in the car. Maybe there was a passenger in the car by this stage and the phone was spotted still lying there in the back and needed to be thrown out straight away. Maybe it pinged when it was picked up and tossed.
If you are trying to make everything disappear why would you keep the license, credit card and phone of a murder victim together and rely on a smallish body of water to keep the secret? Because you didn’t have time to separate, destroy and scatter them well?
I don’t think he planned much or went far that day, hence him being easily found and it all now steadily unravelling.
Just my opinion.