I don't get why it has to be at all about the role itself, the honour of the military, or anything else.
If I'm extended an offer of employment including a $10,000 signing bonus, sign, take the job, receive my bonus, complete the job as agreed, and the contract expires and I go on my way... The company doesn't get to come back to me years later and say "Oh, oops, I actually forgot to have my boss sign off on that bonus I gave you. You need to give it back."
If you broke agreements with your financers on where/how that money was to be spent, that's your problem. Our contract was still valid - you have broken your contract with your financer and you can deal with the penalties.
Seriously. The people who illegally gave away the government's money should be on the hook for repaying it. Not the people who accepted it legitimately and in good faith.
If I'm extended an offer of employment including a $10,000 signing bonus, sign, take the job, receive my bonus, complete the job as agreed, and the contract expires and I go on my way... The company doesn't get to come back to me years later and say "Oh, oops, I actually forgot to have my boss sign off on that bonus I gave you. You need to give it back."
If you broke agreements with your financers on where/how that money was to be spent, that's your problem. Our contract was still valid - you have broken your contract with your financer and you can deal with the penalties.