The last sentence from Sean Cavanaugh's justification for the FontSite fonts says a lot:
You have to keep in mind that holding a copyright does not preclude one from entering into licensing and distribution arrangements as many companies did with URW.
Sean firmly maintains that he has been granted a distribution license to many URW/ATF/Softmaker fonts when he was employed by SoftMaker/ATF. And I remember buying his book when I graduated college in the mid nineties that included many of these fonts in the jacket CD. He's been distributing them for a long time.
Have you considered contacting FontSite and asking directly?