MA -“Is it possible to be menachem someone when he knows that the entire tragedy the occurred R”L could have been avoided if the brother who it occurred to would have listened to his rav & just done teshuva?”
That’s your problem and a lot of others!
The reason we’re in Golus and have Tzarus, is not because we didn’t listen to some Chumros, (if that’s what you meant by Rav,) but because we didn’t listen to the Torah!
We read every year – Chazon, did anyone on that Shabbos think to themselves – what I’m going to do to improve?