AGDInteractive and the former KQ9 project (now The Silver Lining) both received permission from Vivendi to use the King’s Quest material in remakes and, in the case of former-KQ9, an original fan project.
I think other fan projects that start up hope to receive permission as well in the long run, as it’s been proven by those two teams that it can be done. The trick seems to be to 1) have a high enough quality product and 2) bring the project to Vivendi once it is complete or close-to-complete.
I don’t remember the exact timeline, but I think AGDI had already finished their first remake and KQ9 was of course well into development, when both teams were contacted first by Vivendi, who then, through negotations, gave them some kind of license.