Holy moly, grats.
At first I was like what's so good about this and than I was like oh, that boss.
I...have also soloed mythic Eonar on my hunter. Like a month ago. I didn't stream or record it though because i didn't think it was a big deal? I guess I should have? I figured I couldn't possibly have been the first person to do that....I didn't use any speed gear or special trinkets, I think I may have used a single Lightfoot potion? Literally wasn't even trying to break records, I was actually carrying an alt on my second account through the raid for transmog and twink gear XD
I didn't realize this was a big deal either. I soloed this on my enhancement shaman a month or so ago. I'd have to check the achievement to see exactly when. I was able to make it as far as the sisters since my earth elemental hates tanking things away from me so I couldn't keep them apart.
Nobody thinks to say that they achieved something until there's a news article posted about someone else...then there's immediately someone else saying they already did it. Interesting!
First to brag about the kill, I'm sure there are plenty of others could of done this sooner if they wanted to. Besides a DH did it first, so was little reason to do that. I was thinking i could do it 3 months ago when I realized i could click all the crystals on the ship. I would just need to know the spawn timers - DBM would solve that. The only issue really is speed for this as your gear will not really matter, so speed on gear is probably going to be all that matters. you can corruption effect whatever else you need stat wise.