I'll caveat with the fact that again, I'm only representing myself and my own opinions here, not that of any organization, nor are my comments meant to be taken as legal opinions. Just the opinion of a guy on the internet.
That said: I would not be surprised in the slightest if the AG was specifically looking for a "sloppy" case to try to put a nail in corner crossing and raise it when it shouldn't be raised in the first place; and also support the longstanding argument that mapping apps are not allowable evidence to disprove trespassing. The legislature tried to do that this past session.
Everything detailed in the article is just alleged and has not been proved by a jury beyond a reasonable doubt, including allegations that their cameras captured him on private land. Remember: the position of landowners such as this is that even when someone is crossing on a perfect corner, they are on private land.
It also sounds like the ranch manager has a bone to pick with the public (in some ways, that distrust is valid, given the OK Corral incident on Block Management from a few years back).
The AG almost never gets involved in misdemeanor cases. Take that for what it is worth.