"I was really hoping Asylum Rhapsody or someone else would point out Nidoqueen and Bastiodon during the project..."
I didn't mention dex entries like that of Nidoqueen or Bastiodon because they are much more vague in their reference to their young, in a way that could mean either a prevo or not. I went with Banette as my go-to example exactly because is discusses its creation in a way that seems to preclude a prevo. I'm sure that there are other examples, but I don't have all Pokedex entries memorized. =P