lol. why didn't you get the other girls number? things would have been much more easier. I say, bring a wingman and make sure he talks to the girl you don't like.
sorry but the girl who's number you got probably likes you so if you ask for the friends number she will be hurt and the girl you like probably won't go out with you cause her friend like you
so you messed up
you're screwed because even if you got to meet the one you liked then she wouldn't do anything with you because you "liked" her friend first.
and it's full dog to date any body that has had something to do with your best friend,