Brian,
As a furloughed Government employee...I had the time this afternoon to as least figure out how to make your dwarf signal work with the fastrack switch. I had to completely disassemble the switch controller in order to figure out how it works, but I got it done. Really simple...Please see the drawing below. Now to make it work with your DCS system is an unknown to me. But the schematic below is directly from the Lionel controller minus the switches and 1 pair of LEDs.