Must the loss resulting from the buyer's fraud in the price of the merchandise be shared among the three brothers, just as profit is shared, and is it permissible to pray for the deceiver's destruction?

The relationship between the first brother (procuring the goods), the second (financing), and the third (marketing) is called in Islamic jurisprudence "Mudarabah" or "Qirad." This is a partnership where capital comes from one party and labor from another. The agent in Mudarabah is trustworthy and does not guarantee against loss unless it is due to his negligence. The loss is borne solely by the owner of the capital. If the two agents do not transgress or exceed limits, they are not liable for the loss of capital. As for the prayer of the oppressed against the oppressor, it is permissible and answered, provided that the oppressed does not transgress in his prayer.