I've managed to rip a model and use the node groups but for some reason, I can't change the eyebrow color, is there a solution?
...Show what you mean. You should be able to change the color using the little color menu next to the node connection name, if you didn't connect a node to it.
Also make sure you're using the correct textures, and have the correct settings on it. (as shown below)
It should be set up like this, if done correctly:

(the only problem would be 000_000's eyebrows, as they don't have transparency. but since that's
transparency, it shouldn't affect the coloring at all)