Look to section 302 of SCRA. (a)(1)(B) the lease or bailment or personal property, may not be rescinded or terminated for a breach of terms of the contract occurring before or during that person's military service, nor may the property be repossessed for such breach without a court order.
You need to gather all facts in this case. When was the contract signed? This section only applies to a contract entered into before "military service". Was the auto repoed with a court order? If not, he should be contacting the bank's counsel (and possibly his own). Most bank's won't want the negative publicity and will work something out with him. He should also insist his credit bureau info accurately reflect the situtation. If he was late on payments, that is a fact which can not be disputed.