The models I've used don't make typos on variable names that already exist in the context. Typos are not the failure mode, this is literally the easiest text prediction task they can do.

What you guys probably want to do instead is get to a common definition of what a typo is. Personally, I understand it as a typographic error, which is a fancy way of saying a spelling mistake (a mistake on a letter), not a mistake where one use a word for another.

Maybe you meant the latter?

I, for one, have not have this experience with LLM creating new variable names when they already defined one.

Lots of mistakes, but never this one.