We stayed at POR at the end of May and took the boat to DTD. You pass the treehouses on the way and the CM driving the boat told us a little about them. Like the above poster said, they don't plan to tear them down because they can not rebuild on that land because it is considered "wetlands." He said that there was no talk of opening them in the near future. He said that they all continue to be fully furnished and all the electricity is running, including the AC!! I couldn't believe that they were wasting all this money on running AC in rooms that weren't being used. He said the electricity was on so they could turn on the lights at night, partly for security and partly to help light the waterway for the boats.
Of note, some of the treehouses looked like they were in pretty ruff shape.
Hope this helps.