The quarry, I believe, is still on the Avery property, though it may be some distance (not 12 miles) from the salvage yard. Here's a map, but there's no scale to show how far apart the two sites are. The evidence is said to document her route, and show that she left the property the same way she came in. This by itself does not prove Avery's innocence. This isn't a smoking gun per se, but another piece of evidence creating reasonable doubt. Now, the prosecution's narrative needs to explain those 12 miles. So Avery would have to have followed her somehow, abducted her, return to the property with her and the Rav4 (and his own vehicle), go to the quarry, and back to the bon fire, killing her at some point and disposing of her body at the multiple sites, all within the time frame where Avery was unaccounted for (I think before 5pm, and after what ever time she showed up to the salvage yard). All that said, this evidence will probably not result in a new trial (even if it was a smoking gun) because it was discoverable to the defense at the time of the trial; and unless it was hidden through prosecution misconduct, I don't see how Avery's team will be able to overcome that fact. (They might be able to argue a technological deficiency at the time of trial or that the courts weren't willing to recognize ping data as evidence at the time of trial, but the article suggests that argument won't hold the day.)