I was told by a GM who I will leave anonymous to post to the Blizzard forums regarding my issue.
I have evidence showing I completed the requisite quest for the Breaker of the Black Harvest Achievement on 6/18/2013, which was within the expected window to get this title. My only mistake was having in-life issues and a waning interest in the game, so when I discontinued my subscription I not only missed the log in window, but I was not in a head space to follow any news related to this title.
When I returned in Legion I petitioned and was told I could do nothing. The response I got was especially unwelcoming at the time, implying I should have had the foresight to follow WoW news even when I have other things going on, but I revisited this through the GM ticketing system, but have gotten disappointing replies.
I’m going to continue to press this as much as I can,. It may not seem like much, but I have evidence of chat logs from 2013 that corroborate my claims that I couldn’t have edited or forged (Thanks Zuck??) proving that I accomplished this at the time I would have needed to to get the title/achievement.
My Black Temple achievement also lines up with this timing because, as anyone who did the quest knows, the raid is locked to the quest instance until you beat it, which took me a LONG time, specifically until 6/18/13. I then did a BT run to celebrate my achievement, which locked my completion date to the same: 6/18/13.
I deserve this title, I have evidence to back up my claims, and yet all I can be told is that it can’t be verified on their end. I’m trying to provide them external means of corroborating my claims but they just are ignored. You can see the screenshots, but no one wants to work with me to verify this.
It feels like Blizzard is saying, “Sorry buddy, we can’t tell if you’re telling the truth because we don’t care to keep logs for these things, and you might as well be lying to me without evidence. What, you have evidence? I don’t care, we can’t verify this on our end.”
Work WITH me and I’ll show you the logs, you can confirm that this happened when I say it did. I’d encourage anyone else with evidence to try and step forward for what is rightfully yours as well.