To turn off lircd.service permanently:
systemctl disable lircd.service
There could be several running. You will also need to check for lircmd.service, lircd.socket, lircd-setup.service, lirc-uinput.service, and irexec.service. These are all part of LIRC. All of them effect the way key presses are sent through. The easy way to check which services etc. are running is to use:
systemctl list-unit-files
This will list all the systemd units on your machine. You can search by pressing / then your search term.
You will have to stop the automatic restart in udev if it exists as well.
Also there should be several keymaps which can be loaded with the kernel. It is possible the only one loaded and or available is missing the keys you want to use. I cannot remember the command to list the available codes the kernel has to offer. It has been too long.