@altr0n Looking at this: https://github.com/ubports/android_kernel_lge_hammerhead/blob/ubp-5.1/arch/arm/configs/cyanogenmod_hammerhead_defconfig#L1491
bcmdhd is being built as a module. Can you confirm that it is being built? Maybe it's just not being installed. How exactly did you "craft" the boot image?

@altr0n

I managed to get my own kernel compiled, the issue was that I did not have a console argument specified that I needed (I founded it on another post here)

console=tty0

Needed to be added to my kernel command line args.

Hope this is useful to someone in the future!