I still have Becky in Tellville, and need 50 towels, which (like pillows) also do not spawn. They USED to spawn, when Becky was initially introduced - prior to introduction of Donna and this glitch. I know, because I had FINISHED Becky! lol
My problem is unique:
Like I said, I had actually finished Becky. Completely. I had unlocked all of her pictures. All the rewards, and skill points. Done.
Then comes the update that was intended to introduce Donna.
At which point, Donna did not appear in Tellville for me. Instead, there was Becky - AGAIN - and her progress was reset back to zero. No stages complete and all of her photos eliminated from the vault. So I had to start over with her, ie the various stages including strength missions, and when I got to the point of needing 50 towels. They won't ever appear.
When it comes to Donna, however, ALL of her photos (5 in total) show up in my picture vault. The game is basically saying I did her, completely, even though I never saw her once or did one single one of her tasks.
As evidence of this phenomenon:
Once I ever get to finish Becki, if this ever gets fixed, I'll never see Donna. Nor will I gain any skill points from completing her tasks, but that's fine. If I ever get to finish Becki, I will have gotten skill points from the completion of two bosses, even if it's just the same boss twice. The result will be the same as if I had done Becki once and Donna once.
I'm sorry, I normally try to offer more constructive, if direct, criticism, but this time, they done broke this goooood. LOL 
