When Joshua disappeared, what was the weather like? Did they get snow there?
Even if the LE is not needing civilians to help in the search, there is stuff they can do on their own.
Everyone, including those leaving the party and the neighbors, need to check their cars inside and under. Also, they need to check around and under their own trailers. Is there a yard that Joshua likes to play in? What about all those utility buildings and under them? He could have been snake bitten, crawling under them.
Are there any vacant mobile homes? Maybe there is a door unlocked.
Anything.....
Looked on the map and the area seems to be well kept, but then we don't know how far back the videos were taken. It looks like there could be a bridge with posts on each side for water to go under the road, maybe a culvert or a pipe. I'm assuming they already checked that.
What about septic tanks or do they have sewer system?