Those Styluses aren't super easy to get out of those chromebooks, especially when they break like that.... @slinkliechan is on to something, try taking an M4 or an M5 screw (whichever is VERY slightly larger than the body of the stylus, so it'll only bite the inside), drive it into the body of the stylus. and very carefully pull it out of the chromebook. Then, replace that stylus, they're like $25usd right now on most parts sources.