It’s not the origins of words so much as their history. The etymology of a word includes the series of permutations the word went through from the earliest known use up to the present including the definition or usage of each permutation. So an etymologist would very much know the current definitions of both words. The present definition of a word is part of its history.
Try looking up the word ‘nice’ in the OED to see a long list of changing definitions.
Anything is possible. They might be aliens discussing football in a language that just happens to sound like English, but where the words all have quite different meanings. :rolleyes:
Yes, it is not really a joke, it is a logic puzzle. (Although hardly “mundane answering”. No-one, not even logicians, would really behave that way.)
The Batman joke reminds me of a trivia question that a local radio station posed about 20 years ago, to wit: “What’s the first thing you know?”. Listeners called in their guesses for three or four days before someone finally came up with the correct answer. So think before you click the spoiler. Hint: it’s a joke as well as a trivia question. So, what’s the first thing you know?