You have 3 options:
1) Speak with your dean about the school letting you graduate without the CS because at least you have taken it, and you have already passed the CK. No one knew about the CS score processing schedule that was instituted late last year. The school is not bound by any external rules to require that you pass CS before you graduate. Explain that to them in a face to face meeting. Hopefully the school will see the light and make an exception for you.
2) Let the match take its course. Shortly after the match you will get a contract. Sign, seal, and submit the contract. After the contract is completed and approved, let the program director know of the situation. It might create a momentary "situation" but the program would likely be able to accomodate you. You would attend orientation and then some of your weeks of vacation would be shifted to July, followed by some unpaid weeks.
3) Let the program director know about your situation immediately and risk not being given a contract for the 2006-2007 year. (It is a less likely that the PD would do that, but it could happen.)
Think over your choices and make a wise decision.