Thank you I really love your analysis!
I actually thought of a reason the wizard couldn't bring it himself it's because his magic is unstable enough to put magic spells on the rock over long periods of time or if he used teleportation it's too dangerous for the rock. And he needs the boulder in perfect condition So he can make a holy sword for the knight.
Basically sometimes there are no shortcuts and you have to do it the hard way
To be completely honest I didn't think about the colors the way you did but I love it so much it is now completely part of this game and what its meant to deliver. So thank you so much for the insight!