So, we have the word {SorHa'}, meaning "to speak metaphorically".

On the other hand, we can't use klingon words metaphorically, because
we always need to take them on their most myopic, strict, and
narrow-minded meaning.

You are mistaken. Feel free to speak metaphorically. What we can't do is assume that an idiom from another language will work in Klingon.

-- 
SuStel
http://trimboli.name