I think you are geographically confused, Jindabyne is no where near the Blue Mountains.
There a couple of very short push DH tracks, but still heaps of fun, between the dam and Tyrolean Village. Basically just get on the XC trail at the dam wall and ride towards Tyrolean, you cant miss them. The first one you come to is called "The Choad", heaps of little gaps and berms, you don't really need a DH bike, we were doing it on XC bikes last weekend. The other track is closer to Tyrolean, we didn't ride it, but it looks a bit faster and more open. There is also a little set of jumps near Tyrolean.
Thredbo opens for DH on 19 November.