I FULLY AGREE with everything Samantha in Sydney just wrote to you.
About the course, please DON'T DO IT... not only will it be a waste of time and money, but Emirates likes the recruit new people that have never been cabin crew because they train them in a specific way. I think that if you do this course it could even result as a negative thing for you when you apply again.
I have an american passport, forget anything about not making it because you are american. There are LOT'S of americans here. And anyway where was the Open day? Wasen't it in the USA? If they didn't want americans they wouldn't go there in the first place. And anyway it's good to be american so you can do the USA flights, if not you have to apply for the visa and a lot of crew can't or don't want to haha.
It's not only luck, I do belive in fate... and maybe God has something better for you, or maybe it wasen't the right time. Best of luck in your next try
