It'd appear that I have finally after a long struggle, been able to replicate the Elite Guard equipment bug.
(Sorry to those who had to witness my near mental breakdown about it)

It was due to WL NPC system apparently not supporting painted items.

I will be pushing a fix soon, but until then, for those gangs who have elite guards unlocked, please refrain from using painted items on your elite guards guards.

After the fix, if you equip guards with painted items, they'll be given the unpainted version of said item instead.

A side effect to this fix, is that a default item will be assigned to certain slots, if not manually equipped.
Currently that would be: Armor, Weapon 1, Misc 1, each slot equal to the correponding in the default build.

- Lynx