Installing Intel iwlwifi firmware for UNCLAIMED Wireless 8260?
Fixed my own problem
When I saw that the drv.c file was exactly how it should have been, I got frustrated and stopped. Turns out this was a good thing and I needed to keep following instructions. I then finished the fix by running the commands to actually install the backport that I learned about from the above linked post in my question.
cd ~/Desktop/backports-20150923
make clean
make defconfig-iwlwifi
make
sudo make install
This and a reboot was all I needed to get the wireless drivers perfected