Some more on cell phone tower pings and triangulation off more than one tower. IMO this is very important in determining how accurate the new ping data might be. If it pinged off of 1 tower it is not that accurate, if 2 towers it's a bit more accurate but not precise and if 3 or more towers it becomes much more accurate.
Using cell tower triangulation (3 towers), it is possible to determine a phone location to within an area of “about“ ¾ square mile.
http://wrongfulconvictionsblog.org/2012/06/01/cell-tower-triangulation-how-it-works/
Why is this so important? Well it is very important in determining IF B's phone was actually in the new ping area and what the degree of accuracy is in pinpointing it's true location. If his phone pinged off 3 towers we can assume it's accurate to within about a 3/4 mile radius. If it pinged off 4 or more towers it would be even more accurate.
So say it pinged off 3 towers then we can determine that at 1:18am B or his phone was within a 3/4 mile radius of the new ping location. I don't think there is much disputing that. If it pinged off only 1 tower it's not going to be very accurate. Determining it's accuracy would depend on the data the PI was able to get from Verizon.
But just because his phone may have pinged at 1:18 am in a specific area, doesn't mean that was his final resting place. We know he was alive and communicating at 1:10 am so we can assume his phone was on him at that time. IMO it's highly likely that his phone was still on him 8 minutes later. Why did he not respond to that last text? It sounds like (if they were able to triangulate pings) he likely would have had cell reception. If he became deceased or unable to communicate around 1:18 then that is likely an area where he passed on. OR he dropped his phone and continued on. And if he passed on in this area we have to consider that in the last months much of his remains would likely be scattered by animals but they don't usually take cell phones and you would think there would be keys, shreds of clothes or something offering a clue. How close is the new ping area to a road such as Hwy 58 where B could have hitched a ride?