It is a shame to let such a thing go to waste, but I'm thinking that your future training and type in a BE-40 will more than make up for the lack of a CE-500 SIC rating for any possible future employment.
Congrats on the opportunity though.
If you would care too share your journey, we've had a lot of the usual 'best ways to go about.....' type of questions lately from people looking to follow your path.
Maye a new thread in the 'Military' forum detailing your selection process?
USMCFLYR