Disclaimer: there is NO password provided somewhere in the post, you need to get actual firmware/microcode and do some steps manually. Also you need carefuly read the f.cking manuals provided by vendor, manufacturer, ODM or OEM vendor to avoid getting some unexpected results before run any commands or apply any configurations. All steps provided is abnormal and should not be used in prod environment. In some extraodinry cases you simply ruin your whole installation ;)
# you can install this tools OR just use 7z for cramfs unpacking and loop mount for initrd
# also you dont need to unpack initrd
# skip this step if you only keys
trizen -S e2tools cramfs-tools # AUR
# ... or just p7zip
trizen -S p7zip
mkdir sl3000_fw && cd sl3000_fw
7z x sl3000/FRS_x.yy/SL3000_FRSxyy_firmware.jar
Check-in: