Guilt by Association by Gilbert Morris a Danielle Ross mystery

Dani Ross was called home to run her father's detective agency in New Orleans. After she studied the finances and other case records she decided to hire another investigator. Amazingly, an ex-cop came to the agency seeking employment about that time. Though he was something of a maverick he seemed a capable investigator. This allowed the agency to win more contracts which were needed to keep afloat. Dani went to meet a client in a remote location and did not return to the office. She was no where to be found. The new employee, Ben, went in search of her and was himself kidnapped. That was when he found Dani. Both of them joined others being held prisoner in a silo which had been altered to hold people captive. Each day the mastermind, Maxwell Stone, spoke to the prisoners on camera and speaker. He wanted his captives to confess to something they had done but they didn't know what it was. As the weeks passed various people became ill and one died. Lists were made by Dani and a WWII submarine commander, Karl, trying to figure out why each of them were there and what Maxwell Stone wanted from them. It became apparent to all that there was no way out and Stone would gradually kill them all. There must be something they could do to stop him. But what could that be?