These scenery objects are seen by some, but not all. I have two different land class products to toggle between, along with the default land class and none will show these stray structures? As I mentioned before, I have the GEX textures installed, just not the interface, but that should have no effect.
If this is as claimed, a problem with GEX, then the issue should be addressed at the Flight1 forums, where I'm 99% positive of the response you'll get from Mr. Needham...

I have only seen one set of circumstances where photo scenery does not exclude the autogen of the underlying default (or add on) textures. I don't see that with the FSDT photo work.
And in more than one occasion have random objects appeared from some scenery work totally unrelated, many thousands of miles away.
And James, with lat/lon of the four(?) objects it would take about 90 seconds to make an exclusion to get rid of them.