You don't have to be sad, the avatars you created were very good; and a final decision on all of this hasn't even been given yet by the manager and the Sinbad management team, even if you don't win the reward in the end, users in the campaign may use your avatar design if the manager allows it.
A suggestion:
Even though there are winners for Avatars, my suggestion was the possibility of selecting a set of avatars that can be assigned to several users.
Not a bad suggestion, and i believe the manager may consider it after the Avatar contest is concluded.