Wiped T310, no OS, unable to mount internal SD topic

Prior to today, I had not installed TWRP or rooted my T310 device. I believed I followed the instructions to root my device correctly (found here). Going through TWRP, I rebooted the system to install the Superuser package. I then rebooted the system, loaded up TWRP, and began to do a system wipe (followed instructions found here) to prep the flash of the rom and gapps.

I selected the following partitions to wipe: Dalvik cache, system, data and data. The instructions werent clear, so I checked both 'data' boxes.

After the wipe executed, I went to flash the rom and GAPPS I loaded to the internal sd card aaaaand... there were no .zip files. Crap. I went to reboot TWRP and it alerted me that my device does not appear to be rooted. Double crap. Not panicking, I went to mount and tried to see if I could mount the internet SD card to my device. Nothing. Windows now shows a 'Samsung_Android' device but it is listed under 'unspecified'. Reloading the drivers have done no good.

I'm guessing SuperUSer was never installed correctly *or* I did something during the reset.

I, of course, did not perform a backup prior to all of these. I have rooted my devices multiple times and it was always a breeze so why backup now? Weell...
So now I'm sitting here with a nonSU device, with no OS, no backup, and I'm unable to connect my device to Windows. Outside of loading a rom from an external SD Card, what options do I have?