Random fires in/of homes in this area, and a chamber built in this abanonded home just this year?......
Sounds related.
If I was LE I would be checking many other abanonded homes.
First thing I though about when skimming through articles was human trafficking.
If there is no evidence of a crime in this chamber there at least has to be some DNA somewhere. Has to be.
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Yes, we were discussing transit of human beings and this possibly being a temporary holding area until the next transport to take them even further away...
Just one example, (that I think was operative, even in the past, with missing children cases):
Let's say someone in power has the agenda of abducting a child from the U.S. to another country. This person dispatches someone to abduct the child, or was the abductor? They would find in necessary to travel as far as possible from the 1st crime scene (abduction site), probably cross the border, and have a "rest station" until the next leg of the journey begins. They would need a holding area for multiple reasons.
And, I agree. I was saying earlier that there probably were fingerprints, DNA etc. at least of the builder(s), if it hadn't yet been put to use.
Maybe some cold cases can be solved by figuring out who built this. This may have not been a first project.
My guess is that LE is soft-pedaling their request for someone to come forward and admit they built it, by saying perhaps it could have been intended for some other "innocent" purpose, like a movie set.
If it was intended to be a "movie set," then it would have had to be planned by amateurs, who did not understand the need for permits, as other sleuths here have pointed out.
And, if it was amateur indie filmmakers, where the heck would they get the money for building materials, etc.?