Are the guardians of someone killed by mistake permitted to pardon the blood money, given that the deceased was in debt and left a will?

If the deceased owed a debt or had a will, the heirs are not permitted to waive any part of the blood money (diyyah) except after the debt has been settled and the will executed, based on the words of the Almighty: "from after any will he may have made or debt." If they waive it, the waiver is invalid, and the court must be informed of this to prioritize the debt, then the will. It is a condition that the heirs be mature and sane adults, and it is not permissible to waive the rights of minors except with a guarantee for them.