All perfect praise be to Alalh, The Lord of The Worlds, and may His Peace and Blessings be upon our Prophet Muhammad and upon all of his family and companions.
Among the rights of the deceased upon their heirs are: preparing them for burial at death, settling their debts, returning people’s rights to them, executing their will, and then dividing their estate. What was mentioned in the question falls under the rights of others, even if they are among the heirs, and the deceased is not absolved of it unless it is returned to its rightful owners. This is because Allah, Almighty, forbids consuming others' wealth/properties unjustly. However, do not give up on seeking a solution by involving righteous and well - respected individuals who may have influence over them, in the hope that Allah guides them to goodness and correctness. As for supplicating against them, the prayer of the oppressed is not rejected, even if the oppressed person is not a Muslim. And Allah knows best.