Ok so after 10 hours of boosting this with my friend we figured out how to get this achievement
you will need your account and a second live account that don't need the achievement. Have the second account get loses on it for your friend. Once he gets ranked have him stop playing on that account you load your main account and make sure he uses he's second account and do everyrhing as before. Make sure you are both ranked! Ok now what you need to do is with the account that is more the 5 ranks away have that one win and play the game to the end and it will pop. The since the ranked account just lost it will not be ranked mostley so just load up the second account again and have the account that didn't get the achievement get wins till he is ranked. I also learned playing the same account over and over again will make you get fewer and fewer point each time so if you can have multiply accounts.
So what you need to do in short is get ranked and beat some 5 ranks above you. Please not this is not you SKILL Level its your rank position. You can also do this legitly but since the server is going down on the 11th of august you will only find newbies or the top 100 lol.
This needs to be the first online thing you do!
Good luck and if you need me to help just ask!