Is the former suitor absolved from the debt owed to the fiancée's father if he presents used gifts to the fiancée that exceed the value of the debt, especially given that the fiancée sold one of the gifts to purchase wedding necessities, and her family has not forgiven him for the debt and accuses him of injustice?

The ruling on such gifts is determined by custom. If custom dictates that they are part of the mahr (dowry), then they must be returned in full. If the gifts are returned, but the suitor insists on not returning the debt, then he is an oppressor, consuming people's wealth unjustly. It is permissible to supplicate against him, within certain guidelines.