I don't know that Truman's character was spoofing anybody, but the joke I got out of him was the name.
Lionel twain = Lionel train ( Lionel being a popular toy train company)
The address on the house said 22 twain, it was read as two two twain, sounding like choo choo train. Not the most amazing joke, but it made me laugh.
maybe the train reference is alluding to the fact that everyone would be on the wrong track of who did it.

You could send me a private message.
I guess it's like looking at clouds. You see one thing and I see another. Peace.

If you've seen the film, Rene Clair's "And Then There Were None", you would expect it was a spoof of the person who invited all the guests to "Indian Island" and then killed them off one by one. I'm not about to reveal who it was and ruin that film for others who haven't yet seen it.
But speaking of the "actor" who played Lionel Twain", whatever you might think of Truman Capote as a writer, he was no actor.
He was perfect, therefore, as Lionel Twain!

Im ashamed to say I never got the joke until tonight when he said that.