I agree with Elli and will go further. There was never any need, nor is there any need now, to use the word "eudaimonia" in English discussion of philosophy, whether Aristotelian, Epicurean or any other kind, because the word is just the original Greek word for "good spirits," as stated in wikipedia:
Etymologically, it consists of the words "eu" ("good") and "daimōn" ("spirit"). It is a central concept in Aristotelian ethics and political philosophy, along with the terms "aretē", most often translated as "virtue" or "excellence", and "phronesis", often translated as "practical or ethical wisdom"
Extending the prior recent comments about there being no bright line distinctions between men and other higher animals, there are no bright-line distinctions between Greeks and other humans. No matter how high a regard I may hold for Epicurus, he was a human being just like us, and he spoke an ordinary language just like all of us do, and unless and until he (or Aristotle or some other philosopher) specifically designated a technical term as having a technical meaning, we should presume that a word he used had the ordinary meaning and significance that it had to ordinary people. And so far as I am aware they did not - it is just a "catch-all" term that euphemistically describes what people regard as a good life, but that statement in itself "a good life" tells us nothing whatsoever.
To leave the word untranslated and focus on it as something mysteriously untranslatable - as in this video cited above- is just more woo-woo by philosophy teachers designed to hide the ball and imply that they themselves have access to some kind of esoteric wisdom that normal people who don't speak Greek do not.
And I would say the same about ataraxia and aponia - I would assert that "absence of disturbance" and "absence of pain" contain all the precision that those words have ever meant to convey.