That's a problem I've seen with other WR properties in Argentina for months. For example, do a search around Lujan, and the first two hotels (HJ Lugan and HJ Pilar) never show availability on WR's site (though they do show availability on third-party sites), and it's been like that for months now.
So I'm not sure what's going on, but it might not mean the hotel is leaving. You might have call WR on the phone (and maybe elevate to a supervisor?) to get a decent answer.
(In my case, I found through reviews that the HJs near Lujan are far from the best hotels in the area, so I stopped caring that they never have availability. And that's why I didn't look further into it myself.)