Why can't I get two Dell touch screen P2314Ts to work with my Surface Pro 3?

[Windows Central Question]

I have a dual set up of two P2314Ts running through the Surface Pro 3 and the Surface Pro docking station. The touch on one of the monitors (primary) works fine. Touching the other monitor shows the touch feedback on the primary monitor.

We've already tried uninstalling and re-installing the monitor drivers and the Cool Touch devices. We've tried the Tablet PC set up for the monitors, but it will not recognize the second monitor. It states that there are no touch options available.

* What is the 20 digit alpha-numeric monitor serial number? <redacted>
* What specific computer model? Surface Pro 3 i7
* What operating system? Windows 8.1
* What video card? Intel HD Graphics 5000
* Video card driver version? 10.18.14.4170
* What video out ports are available on the video card? Mini Display Port
* What video out port are you using from the video card to what video in port on the monitor? mDP to DP on both
* What cable are you using to attach the video card to the monitor? mDP to DP. One is plugged into the docking station and one is plugged directly into the Surface Pro 3.
* What windows power plan? Balanced
* Press the monitor Menu button to open the monitor OSD (On Screen Display). The bottom of that screen should show a resolution. What is listed? 1920X1080 60Hz on both
* Was the monitor purchased from Dell or some reseller? Dell

 

[jmshub]

I hate to ask the most obvious question, but I gotta start somewhere... did you plug run a USB cord from the monitor to your Surface? The touch controls run over USB.

If you have, go into Device Manager. Do you see the touchscreens installed on your surface?

 

[pagerond]

Yes, I have both of the USB cables plugged into the docking station. I even tried it with one plugged into the Surface itself, to no avail.