You are correct XYZ. No one will be able to build a SH on that location since it is right at the Place of Power and the closest one can build a SH is at the edge of the woods. There are other locations on the field that no one will be able to get for the Pioneer Achievement because of the same reason. Someone is parked these spots and have not been in the game for weeks or months. AND Yes, they shield these towns for years to come. Why? We can't destroy the town out of the spot. One can only be moved by Exile or by the person who owns the town. Other locations already have SHs around them with a MIA Town sitting on that spot, and I seen a few of these Clan owned SH where there are no active members in the clan.
To make matters worse, PP came up with the idea of making it even harder for us by adding to the rules that your town must be at a certain lvl before you can even try to get that Pioneer lvl.
In short, you will just have to wait until PP makes changes to these situations (Like that is going to happen), or wait until you have a CvC or KvK where that location is open, or at least has an active player on it who might move if you ask them nicely, which is how I was able to get a few lvls myself.
BTW: I'm also stuck on the same lvl as you, and been for over a month.