I just got home from work a little while ago, and was going to post to second this, that regardless of how you felt about this, that you absolutely must not tell him. I now see that apparently one way or another, you’d intended it get around to him, as either he posts here or a lot of people who just happen to know him - and could identify him from your description - do.
You’d phrased your initial question as a matter of manners, not feelings. I’m afraid a huge mess of both, towards him at the very least, has been made.