I'd agree with this where face-to-face interactions are possible. Never going to be effective on the internet. The written word can be construed very differently than the spoken (and witnessed) word because there is no other context (body language, eye contact, intonation, etc) to help convey the message as it's intended. And of course, folk become far braver behind the safety of a keyboard, just read any troll posts.where I'm from when you have a problem with someone you speak to them directly, not through mutual contacts.
can you pm him directly and ask if he has a problem with you?