Chicago routers and Genuity estates

I really hate to do this but I have no choice. IUCC terminated its services at the Genuity colo site at 216 W. Jackson, Chicago in May 2002. We had a financial disagreement about the final bill and Genuity refused to let us remove our routers from the site until our bill was paid. We finally agreed on final payment and we sent that in April 2003. The check has been cashed, but no one now replies to any of our letters (http://www.genuityestate.com/). So until we have a letter allowing us to remove our 7500 routers from their colo site, they are held hostage. Has anyone else been stuck in this situation and what have you done to get a letter of release from Genuity Estates? Thanks, Hank