Can [the Scorpius turret] be slaved to the pilot if there's only one person flying?

If you slave it, like any other turret, any other remote turret, it would be the same functionality. So if the pilot chooses to do that, if they want to solo it, then it would be slaved and it would be locked in the upper position in a forward arc where you can look, which is pretty much the consistent rule for all scenarios like that.