HELP ANYONE, my friend is feeling guilty.

So a friend of mine was playing Warzone ( A BR online game) while he was playing, he kept getting killed in the sky by a player that was on top of a building. He opened his mic and said the three letter abbreviation KY and S (only said the three letters) My friend didn't mean to say it, and he feels bad about it too. He doesn't have ill content to the player and wishes him saftey. I tried to make him feel better, but nothing helped. The question is, how can I get my friend to feel better, and should he be this worried?​