I think you should write an explanation letter and include a copy of your contract. Copy, because this letter can be lost and not connected with your application and then you will have a problem to get it once again.
Mention in your explanation that the original contract will be provided upon request (I am sure, if they will consider it, they will ask you to include the original with your meds and PCC to VO, not to CIO).
One more thing, write down on the envelope of your letter/package "For consideration of application Mr. Your Name received by CIO on date". It will help them to connect it and through away the letter or simply return it without consideration.
Good luck and fingers crossed for you!!!