No pitchforks. Via dependancies is the way to go.
I had an idea about somehow still making use of /customizing Deadlock's assets without it being considered derivation, but I do not advocate this as a form of circumvention.
You can prototype completely new assets in Data stage by referencing other assets (assuming you know their file path and sprite size ahead of time) and using the game's included tinting/layering ability to combine several different graphics for a final result.
Example:
1. Your mod references a BY-ND-NC mod via dependancy. None of its assets are in your mod.
2. Your mod creates a Data stage prototype of all the customized entities you want to make. Some of these reference a BY-ND-NC mod art asset as a base graphic via file-path-reference.
3. Your mod physically includes your own and untraced tints/blending overlay art asset files.
4. Your mod then references your own assets as blending/tinting layers as it prototypes the custom assets.
The nicer you can match and align your overlays with the base referenced asset, the smoother the result.
The kicker is that none of the dependancy-asset packs are actually in your mod. They are literally combined and layered as the game loads.