With Emrakul, the promised end being banned, I was curious in knowing if that solely meant it can not be in your deck and/or sideboard? And if Coax From the Blind Eternities would be a legal way to play it?
Correct. A card being banned means it cannot be in your main deck or sideboard for a Standard event. By extension, this means Coax From the Blind Eternities cannot grab it, because in organized play "own from outside the game" means "from your sideboard."