It could not work, but if I were you, I would try the following : use a pencil, like HB or the like, put as much graphite powder from the tip by "coloring" the screws with it, think about when you where a kiddo, you probably put that stuff all over you finger after scribbling or doodling on a piece of paper.
Gently blow on any excess and find a mate clear coat to put over it, with very light dose, this will prevent the graphite from coming off.
Only problem could be the lack of adherence of the clear coat due to the graphite powder, but worse case, you just dunk the screw in alcohol and use the sharpie again (maybe a dark grey sharpie this time ? or a mix of two color ?)
Yeah, I am debating how much I hate the black screws vs having them dark grey. i like the dark grey paint pen idea. The issue with paint pens is the finish is glossy and not matte.
On the pencil idea, the paint will stick to the graphite and not the metal, so it's most likely a temporary solution.
I really just wanted to knock out those bright silver screws that screamed "rep" and the matte black certainly has done that. I still have the 4 brights holding the front deco in place, but I didnt want to get inside the watch today.
The reality is anyone who knows anything about RMs is going to see that balance wheel not moving. But on the wrist, I think I am 98% there. Heck, most people have no idea what a RM even is, and until a few weeks ago I couldnt tell you if the screws were supposed to be black, grey or whatever.
I really like the NTPT as it looks 100% what I remember from the boutique and vids from YT. Really is next level and is amazing in the sunlight.
This is my favorite watch right now.