Meh, Stuff happens. I've ripped aggro from tanks before as has everyone. Not your fault the healers couldn't keep the tank alive and you were next on the aggro list. What was the second tank doing? Not stepping up that's what. Someone needs to be second and if it's not the second tank it's going to be a healer or dps by default. Just a bad group, nothing you could do and what you technically could have done, you're aware of and have already learned from that.

Second group sounds like they were trolling you. Shirking you for attacks and rescueing you into mobs. Surely that's reportable? Nothing you could do there since those players went out their way to target you for their silly troll games.

Just put it down to a bad run, move on and hope for a better run/group next time.