“He likes to collect things, so surely he’ll have John Darling memorabilia!” seems like a bit of a stretch to me, even by Westview logic. I would’ve liked a line about how Mitchell’s dad was a newscaster, or that Mitchell was comforted by watching the show after he quit Batom. Just something more than “he collects stuff, so he’ll have what you want”.
And that is quite the strange looking spaceship that Phil drew. If I didn’t know that’s what it was supposed to be, I really don’t think I’d ever be able to tell.