I don’t think emulating shame (in the sense of a computer printing statement that look like shame) and real shame have a cross-over line, they are just totally different types of thing.
Feeling shame requires feeling. I can’t prove that an LLM isn’t feeling in the same way that I can’t prove that a rock or a graphics card isn’t feeling.
We do, you might find legal sentencing guidelines to be informative, they’ve already been dealing with this for a very long time. (E.g. It’s why a first offence and repeat offence are never considered in the same light.)