Are there any real-world examples of malamanteau?

A great subcultural linguistic movement is centered on this very concept: it's a specific Canadian and P/NW slang associated with tech, mechanics, and tradespeople--its apotheosis is a prolific youtuber known by the moniker AvE. There's a sensational glossary at: https://bumblefuckerytoenglish.com/

Consider the self-explanatory, but crisply inventive: prefamulated

Procrasterbation

Shituation

Stealership

unobtainium

Kanuckistan

Sterling examples all of this inventive and emergent ("emectant?") trope in action! A quick visit with a curious mind (a "Quisit"?) is well worth the price of admission (So you don't need "Primission" first!)

Yes. Malamanteau itself is.

A malamanteau is a neologism for a portmanteau created by incorrectly combining a neologism and a malapropism. It's itself a portmanteau of malapropism and portmanteau. It's also a malapropism of portmanteau. It's also a neologism coined when the comic was made.