Hello! I can’t get started on the Tides Of Vengeance campaign! Nathanos doesn’t have the quest, and Sylvanas isn’t in Orgrimmar… I completed Ready for war, all of the zone quests and pre-req achievements- https://www.wowhead.com/attunement#us-bleeding-hollow-ìwontheal
but cannot seem to find the quest to start tides of vengeance to continue unlocking the pretty trolls. Any help would be appreciated.
Have you looked over this quest list?
link: https://www.wowhead.com/achievement=12509/ready-for-war#comments:id=2574105
It seems your posting character stopped midway through and needs to do the following quest to get back on track:
link: https://www.wowhead.com/quest=51592/making-ourselves-at-home
One of the requirements for starting Tides of Vengeance is that Ready for War must be completed on the same character that wishes to do Tides of Vengeance.
Excellent sleuthing.
Iwontheal, it does appear that you abandoned “Making Ourselves at Home”, which is part of Ready for War and the The First Assault storyline.
If you look at the comments for Ready for War there should be a list of quests you need that should allow you to track your progress. 
I appreciate the response, thank you!