Since WotC owns all of the IP for AoW, ST, and Maure Castle, they could easily decide to publish such compilations themselves, and make all of the profits from such, too.
It seems, though, that WotC is more interested in publishing original material of their own creation (WRT d20/OGL third party content), so if they follow the same course as they do with the rest of the d20/OGL content available to them, they wouldn't publish this "foreign" IP either. Of course, this IP is set explicitly in Greyhawk, so perhaps that fact makes WotC perceive it in a a different light than purely-external IP that has no basis in a WotC setting.
Thoughts?