My nephew asked my husband to pay his pawn ticket and told my husband if he were late, the pawn shop would just "add a penalty"for a month; my husband went to pay and the item had been sold
I'm not sure of all of the byplay, here.
Did your nephew give your husband the money, or was your husband paying for it out of ya'll's money? You're husband talked with your nephew and made an agreement to get the item from the pawnbroker?
Did your husband go to pay the pawn ticket late? After the date the penalty would have been added?
Based on what you've said here, your nephew is definitely guilty of not providing accurate information. IMO, it's up to him to really understand the rules when he decides to pawn something.