A CTR is required when a cash-in or cash-out transaction or transactions is/are completed on the same business day BY or ON BEHALF OF a person.
FinCEN has said in its FAQ on CTR filing that a deposit to a jointly-owned account is considered made on behalf of each of the joint owners. Therefore, the $2,600 deposit in your scenario was made on behalf of both husband (H) and wife (W).
W was the conductor of both transactions, which means that both deposits we completed BY her, and you have to aggregate the deposits to determine whether to file. Since the total of $10,600 a CTR is required.
When completing a CTR, you must provide information on each identified person conducting the transaction(s) and on each person on whose behalf the transaction(s) is/are completed. You will complete the CTR to report that W conducted the transaction and that it was completed on behalf of W and H. Both of them are identified.