Thanks for the tips and suggestions Evan and Rafael. Oddly enough, I thought that this particular panel didn't use the DSI connector for the touchscreen because it only functioned properly when connected through the pogo pins. However, it turned out I had a bad wire.
Looks like the 10.1" panel is similarly wired to the official one and works in the same way, with the FPC cable for both video and touch, and a set of wires for power.
Unfortunately, I've also only been able to get the 64 bit version of the drivers working on a fresh install and couldn't get the display working with the original provided SD card, so I'm building it fresh. I ended up not using the pi username without realizing the installer assumes 'pi' in some cases such as making directories in the pi home folder.
Any chance there's a way to configure this differently without much issue or is this assumption made in too many places to change easily and I should just reinstall and be stuck with the default username of pi instead?
Scott W1LD