agree with Jac...move all of the funds to the new account (we call that an "account swap" at my bank and do this frequently). Make sure an NOC is done, and make sure the husband knows to contact anyone who was depositing to or drafting from his account that they should change to his new number.
If you don't have the ability to do as above, then i would return for no account/unable to locate account.
Not your fault he neglected to notify the sender of his new account number, and if that delays his getting paid for a couple of days, that is his issue. wife being overdrawn is not the husbands concern, having access to his money is.
Anything else you do puts your bank in a sticky situation between feuding family, no where you want to be (in fact, i'd consider closing both accounts as soon as you are done with this mess).
In no way would I post to the incorrect account, leave a portion in that account to bring it whole (you've already admitted it posted there in error and is not his account) and give him the rest...no affadavit will give you the protection you want when your representative gets on the stand and admits to knowing it was put in the wrong account but...
Just my opinion
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