I know it's a year later, but I got here by a Google search this morning, and I figured maybe others would in the future.
I had the same issue in Moonlight Falls, with werewolves that aged up. (These were the ones that were in the world already, I did not create them or change them into werewolves.)
I have discovered, after messing around with a lot of the suggetions in this thread, that for me the solution was very simple:
I used MC to take my Sim into CAS, changed him from werewolf to human. Then I saved, left CAS, played the Sim for long enough to check everybody's relationship panels to make sure the game registered him as human now.
And then I took him back into CAS and made him a werewolf again, and immediately he had a werewolf face I could switch to and it looked fine.
I just thought I'd necro this thread just in case anybody else runs into the problem like I did and finds this in Google.
