"A Christmas Story" Q for movie mavens

[SportsFan68]

Here's what IMDB says about Adult Ralphie narration, which intrigued me enough to do a little googling:

Jean Shepherd ... Narrator / Adult Ralphie, Man in Line for Santa, Voice of Santa (voice)

Rest of cast listed alphabetically:

. . .

Daniel M. Pinkwater ... Adult Ralphie, Narrating (voice) (uncredited)

Here's what Pinkwater says:

Yes, sure, of course, it was Shepherd himself. I don't even sound much like him--similar regional accent and pitch maybe. No doubt the people who compiled that database had at best a foggy recollection of what Shepherd sounded like on radio, but had heard me. Shepherd was, or thought he was, often ripped off. He claimed that the Jason Robards character in A Thousand Clowns was him, and the filmmakers had stolen his life. (Why anyone would identify himself as similar to the character, charmingly played by Robards, but a selfish, immature, annoying pain-in-the-neck, is beyond me.) Also there was a TV series that bore certain similarities to A Christmas Story with no credit to Shep. There's a certain consistency in the IMDB people getting it wrong.

My question is, what would make the IMDB people invent Pinkwater as the narrator?

[TheCalvinator24]

imdb is somewhat wiki. Users can edit any of the info. I think they do have editors who double-check things, though.