my eye is getting worse and worse...
anyway if it's green, then:
- shading with a red/redbrown(VAC-HullRed/VAC-TankBrown for example, VGC-SepiaInk if you want to stay with VGC and inks) and highlighting with a yellow (Ivory again, vgc-off-white is similar if you want to stay with VGC, but the plague brown is a yellow shade too) would work.
This is basically the same what you thought about, but: Smokey Ink has a bit of a textrure, so instead I'd use sepia ink (similar shade, no texture), highlight(Ivory) is much lighter. The plague brown would only make the Grey it more yellow, but will not change the lightness enough imho.
- or if you want to go a colder: shade with blue (dark sea blue) and HL with yellow (ice Yellow (cold yellow, bit greenish hue))