C5519Q, DDM support, multiple sources, #2

Referencing this thread.

I just purchased a C5519Q and am trying to get the multiple input sources to show up on the screen as virtual monitors. I know Dell and LQ 4K monitors have this capability by way of software/drivers where you can arrange multiple inputs as virtual monitors on the single physical screen at the same time. 

Ideally, I would like something like 4 inputs in a grid like this: (or other formats as I want to split them up)

Displayport | HDMI1

HDMI2        | VGA

or 2 inputs side by side:

DisplayPort | HDMI1

I can't seem to find out how to make this happen with the DDM. I see "Span Multiple Monitors" option but that's greyed out.  Maybe there is a different driver/software to make this happen?

Thanks!