Tough Love Achievement Help!!

[JordanNgamoki]

Hey guys i just finnished the game but, stupidtley continued doing the main quest line with out saving the six million dolloars saving the money was the easiy part i just carried on with the game anyways after i done that i couldnt get the tough love achivement! so what im asking is do i reallllly have to play though the whole game again just to get that one achivement or if i play with someone else whose just about at that point and complatae the game with the full money and army total can i get the achivement through them??

Thanks guys

(Gamer tag) JN Logic