We figured it out.

After stressing out like crazy we've finally figured out what we're going to do about the $20,000! We're going to actually put it on another credit card to get the $150 worth of rewards and then we're going to use the check from CitiBank to pay off the credit card instantly.

I'm sure it's probably money laundering at it's best. But the reality is we're just trying to make all of this work and the inconvienence of CitiBank taking so long to process the check sucks!