Translation error?

Next exemple of translation:

French version:

- Ben: Et là…patatras !
- Marco: Patatras?

English version: 

- Ben: And then... kaboom ! - Marco : Kaboom ?

Meaning of this word in french-english dictionary: 

https://dictionary.cambridge.org/dictionary/french-english/patatras

patatras- indique que qqch tombe en faisant beaucoup de bruit

 -crash

Patatras ! Tout s’est effondré !

Crash! It all collapsed!

Unfortunately, the word kaboom could not be found in the same dictionary, but I found it on another website. https://www.urbandictionary.com/define.php?term=kaboom

"The larger version of boom.  Boom is just a "boom" while KAboom refers to the "WOW" effect verison of boom. Something truly boom, becomes kaboom. Meaning an even larger boom than kaboom. "

The situation is different from the previous one, but we also deal with a translation other than the rule would indicate. If the dictionary  says that the translation of the word "patatras" is "boom" or simply "crash", why the translator decided to give this expression a stronger emotional charge than the original french version? 

What's more, the word "kaboom" does not even exist in the dictionary, as the internet indicates it is a colloquial word, used in speech, probably between young people. Unfortunately, I don't have English language sensitivity, but I think that the word "kaboom" is different for English than the word "patatras" for French, and even "kaboom" simply sounds strange in this person's mouth in this situation.