I agree the promoter doesn't know crap, but on the other hand I firmly believe that DT would not sign on to do a festival at that time, and not fully plan to have a single ready by that time to play. And if they do plan to have something ready by that time, they will.
It would be very unlike them to go out and do a show without having the new album in the can.
In short, I don't put any stock in the promoters, but knowing DT, I'd put faith in them playing a new song.