What if the playground is where all of this started, and where it will also subsequently end?
Alex could have been location scouting quite a bit before Entry 4 and 70, while filming the bulk of his Marble Hornets project, and he had happened to film in the wrong place at the wrong time. That’s why no one knows where the playground is. Since Alex was driving a considerable distance, it could be anywhere.
The lights, in the dark, form a circular shape on the ground, which has been used to represent The Operator on numerous occasions. The circle with the X through it, the 0’s constantly appearing in TTA’s videos…
Let’s not forget that the body of the man (and Tim, who was alive, eventually) was transported to a place that fits this exact description, both under The Operator’s direct influence.
Let’s also not forget that there are many lightposts around the playground, just like there were many holes, also circular, in the forest, where the tapes were found in the first place.
When, and if, Jay finds out where this place is, he’s going to have to find the exact spot, and it will be hell. Because, at that point, every character that isn’t dead at this point may be converging in.
Alex knows where it is in the first place, and Hoody will be following Jay (and perhaps Tim), obviously.
But whatever happens after this could be many things, and I will end this post here because of that. I don’t want to go extremely far with this.