Nope. Tried that. However, this does work. Found it in this forum in a somewhat related post:
M581 Z S1 T0 ; invoke trigger 0 (i.e. M112) when a rising edge is detected on the Z endstop input
You can do this for any endstop, XYZE, so I imagine you could use the E3-E6 endstop inputs on the Duex as well if you wanted.