Let’s get one thing out of the way: it’s not normal to stuff $100,000 in cash into a suitcase and then check said suitcase on to a domestic flight. It’s extremely weird, in fact, not something you’d expect a typical person to do in their lifetime. However, doing so is emphatically
That process requires a lengthy and expensive court case and even then sometimes they don’t get the cash back.
Also even if they give an immediate explanation to the officer they are pretty much guaranteed to take the cash anyway. The cop has a financial incentive to do so and will assume the victim is lying.