The article says R2 doesn't switch it back to green, so I'm thinking navigator can't switch it to another color either.
Navigator doesn't change the colour, it lets you change to a different maneuver. That maneuver may then have a different colour and there's nothing Stay on Target can do about it. The process would be:
1) Reveal dial as (for example) a 2-straight.
2) Use Stay on Target to switch to a 2-turn. The 2-turn is treated as red.
3) Use Navigator to switch to a 1-turn. The 1-turn is entirely unaffected by SoT, so it stays white.