the solution is easy, pre-order like ten copies, then sell the keys to friends fo' some sweet sweet profit if it works out (hell, wrangle 5 bucks of them for a copy, and you stand to make an epic profit). if some people were to do this, the devs could possibly reach their mark and everyone gets a cheap game.
if not, you've given a not so significant amount of money to charity, i know i've spent a lot more on things that were a lot less entertaining than this game looks to be.
however, i still believe that knowing more details about the charity in question would be good.