> Shockingly, Pinky was the one who ultimately answered the question correctly, and it's also shown that Pinky can read, whereas the Brain can barely write his own name.

Pinky doesn't answer the final question:

https://www.youtube.com/watch?v=Bgt1X6qXTKs

And I think the way Brain wrote his name was a parody of how Jeopardy guests can get extravagant with their signatures.