He clearly stated the reason in the note. Basically, if you had channel with his node and your node executed a penalty transaction because his node broadcasted old state, he asks for the penalty funds to be returned. My situation was much better in that I only executed a wrong command that triggered closure of all channels. I wish him the best in untangling this situation, even reading about it brings PTSD with LND to me 🐶🐾🫂