It's pure coincidence that he was found relatively quickly. Is the trail known to be used by traffickers? How far from the main road is the location?
IIRC, they found him on Friday morning. If he was in school and was killed on Thursday evening, then teachers would have noticed his absence on Friday.
I wonder if there were any clothes found on/with him. The mother who wrongly identified him would have also noticed familiar (or in this case unfamiliar) clothing.
ETA: Approximate location on the map is shown in the video in this article:
Hunt continues to identify body of boy, new picture released
It is close to the main road and there are homes nearby.
"
The victim is between 8 and 12 years old, 4’11” and 123 pounds. "
I checked averages and his height is about average for a 12 year old; weight is above average for this age.