So then how would a perp negotiate this same rugged terrain with a kidnapped 7 yr old Kyron? If Kyron was walking he wouldn't be able to walk in this terrain. If the perp was carrying Kyron and trying to negotiate this difficult terrain then that seems even more difficult.
So they walked and then left no evidence, no trace, no one saw anything, no one heard any struggle and there was no scent that any of the dogs picked up on?
Doesn't seem very probable given the reality of the terrain.
IMHO Kyron didn't WALK anywhere past the parking lot. I believe he got into a car with someone he knew very well. I don't believe this was a stranger at all.
Right now, I'd say that I'm leaning 45% towards a stranger or casual acquaintance abduction, 45% towards stepmom and 10% Kyron walked away on his own or was abducted by a family member other than stepmom.
The dogs didn't pick him up inside the school or outside the school, two locations where he is known to have been.
That he was not found by SAR personnel or dogs means, well, that he wasn't found. I think there is a low probability chance that he is somewhere out in the rugged area and just not found.
Thinking about searches in general, every search involves covering territory to a point where there is a reasonable certainty that the person/remains are not located there. In general, the more territory that is covered, the more likely it is that something is missed. In Kyron's case, that 2.5 mile circle from the school includes nearly 5 square miles or 3200 acres of territory.
The type of search with the highest probability of not missing anything is a search conducted by trained personnel on their hands and knees, moving shoulder to shoulder over the territory. That is also the most personnel intensive and slowest type of search. It isn't practical to carry out over areas of more than a couple acres.
The type of search most likely to miss something is a search conducted from a motor vehicle. People think they've seen everything but the reality is that they really can't, even if they are only going 5 mph. That 5 mph translates into a 12 minute mile, which is a jogging pace for a human being. I doubt there is anyone who could effectively examine the landscape while they are jogging on foot; driving a vehicle does not magically improve eyesight.
Somewhere in between the two extremes are searches carried out by trained SAR personnel and dogs. That means that, with the best training and intentions in the world, there is still a small possibility that they have missed something.
I think it is most probable that Kyron left school property in a vehicle. Whether that vehicle was driven by someone he knew, I do not know.
While some have said he would not have gotten into a vehicle with a stranger, I believe it is possible he walked out to a vehicle willingly, perhaps to help someone. If he didn't enter the vehicle willingly, he was a physically slight kid (50 lbs) and would not have been difficult to physically overcome.