I just got it to work.
It turns out nDisplay supports some PostProcessing.
With
OutputRemap, you can control the way the 2D image, generated by nDisplay, maps to the 2D area of the application window
So I used the example from the article, and the following OBJ as remap
v -1.000000 0.000000 1.000000
v 1.000000 0.000000 1.000000
v -1.000000 0.000000 -1.000000
v 1.000000 0.000000 -1.000000
vt 1.000000 1.000000 0.000000
vt 0.000000 1.000000 0.000000
vt 0.000000 0.000000 0.000000
vt 1.000000 0.000000 0.000000
f 1/1 2/2 4/3 3/4