Yeah, the kid seems like a spoiled brat, that is why I wanted him to learn a lesson...
About the trade:
It's good that you traded a Maru 3x3, not 4x4 lol
I'd feel like crap solving a cube that someone would not have traded had he known its worth. But he does sound like a jerk..
I'd just tell him the truth and offer to tutor him about cubing for a good hourly rate
And for people that say to help him find a method, no.
If he can find out one of the best cubes there is and a site to buy it from, it should be really easy to search up "how to solve a rubiks cube".
Also, for people that want them to become friends so the spoiled guy might buy a Haiyan Mem. for Will, also no.
It seems like you just want Will to become friends with the guy just to use him to get a cube, which imo is worse than ripping someone off.
Getting ripped off may teach you a thing or two.
EDIT
500th post. I hope it's a good one.