Just FYI, I keep noticing this problem in the last 10 or so versions that hit extras-devel:

The included-in-power-kernel paths to the injection-capable wifi driver modules is:
/opt/packet-injection-modules/`uname -r`/compat.ko
/opt/packet-injection-modules/`uname -r`/mac80211.ko
/opt/packet-injection-modules/`uname -r`/cfg80211.ko
/opt/packet-injection-modules/`uname -r`/rfkill_backport.ko
/opt/packet-injection-modules/`uname -r`/wl1251.ko
/opt/packet-injection-modules/`uname -r`/wl1251_spi.ko

Note that the .ko files are all in that same directory - not in a bunch of different sub-directories, as was/is the case for the backport-modules package. Your latest (well, I last updated about 6 hours ago) version in -devel contained a very neat* script to get the 'correct' file path to the modules, but it would still fail on a device with kernel power 51 without a redundant install of backport-modules, because your wlan-load1.sh script still contains all the subdirectories that applied only to the backport-modules package.

*But honestly, I think the get_wlan_path.sh script should at least be reordered. (And either way you'd have to change your approach, based on the above information, if you wanted to find the directory dynamically.) This is because with power-kernel v51, there's going to never be a need for backport-modules package, so once kernel-power v51 or some stable consequent version there-of makes it to extras, you won't need to keep checking for backport-modules' paths to the modules. Only very odd, unusual setups will exist that could possibly contain injection drivers at the backport-modules paths, without also containing them at the kernel-power 51+ paths. So the logical thing would be to put the check for the kernel-power 51+ paths first, and then only if that path's not found, check in the backport-modules path. The way you have it now, every time you go to load the drivers, it'll check the less-likely-to-be-widely-used-in-the-future backport-modules path, and only then check the built-in-to-kernel-power path.

Not saying you need to fix this now - devel is devel for a reason and I'm happy to tweak the shell scripts myself into working order every time an update happens, but I presume it's something you'd want to fix for when you push it down to extras-testing/extras.