Kid, I think you just may be SOL.
People were reporting trouble getting a room back in Oct/Nov. The online system wouldn't work and if you called the Horseshoe/Caesars reservation line you got to a call center in the Philippines and got to talk to some very nice ladies over there who, bottomline, couldn't help you out. I even contacted GS and no help there either.
For a while there was a ginky way to get a room by clicking on the name "Horseshoe" in the banner ad at the top of the page of the DCC home page but even that does not seem to work anymore. I suspect the ongoing hotel renovation has a significant number of rooms out of commission this year.
Lou Figueroa