Did a little digging and I found:
cateee.net/lkddb/web-lkddb/PANASONIC_LAPTOP.html
talking about modules which lead me to search my computer.
I found Panasonic in:
/sys/class/backlight
/sys/devices/virtual/backlight
/usr/src/linux-headers ... /include/config
/sys/bus/acpi/drivers
/sys/modules
//etc/acpi/events
Do not get excited about acpi events, try this in a terminal:
you@yourcomputer:~$ acpi_listen
It will show the events as keys are pressed, notice that the
light keys get listed, the keys we want to work, don't.
So then I found this:
https://github.com/heiher/panasonic-hbtn
Downloaded zip, ran make, no love.

But its a clue in the quest to make these darn buttons work.
I will document any findings here, feel free to help with clues or a solution.