Earlier quoted context omitted.
What you are describing is also known as an eggcorn. https://en.wikipedia.org/wiki/Eggcorn
An eggcorn is a soundalike though, isn't it? Deliberately altering idioms to catch people's attention isn't an eggcorn IMO.
Not necessarily, you might be thinking of malapropisms but yes probably a closer word would be the general term: protologism.
Another commenter added some useful info on the evocative alteration of metaphors [2]