Your #2 point is wrong. Garrosh warned the AU horde and they turned away from the fel, except Gul'dan.No, its not the right decision.
WOD proved that even with the warning the Orcs will flock towards the fel just like most of the eredar did.
Drop your bias man, respect the story for what it is and recognize that there were no winners in this turn of events and no decision was completely the right one.
Even if what you say is true, the Draenei tried many worlds, inhabited or not and in the end they crashlanded on Dreanor.
You are running in circles and pushing the goal post.
Fact is the Draenei were running for their lives and just wanted to be left alone.
WOD proves two things:
1) Orcs would inevitably start killing the Draenei demons or not.
2) Orcs will fall to corruption regardless of being warned or not.
These are facts. You cannot debate them. It is established lore, and I love how this thread of how the Horde with a history of violence could move forward in a more positive way has ended in a topic where some ardent Horde players are blaming the Draenei for trying to survive.
Simply. Amazing.