What should be done with a financial trust that could not be delivered to its original owner or to his brother who was supposed to receive it, and is it permissible to give it away as charity?

Whoever bears a trust must fulfill it to its owner, for Allah the Almighty says: (Indeed, Allah commands you to render trusts to whom they are due). And it is obligatory not to accept a trust if you know that you cannot deliver it. Seek Allah's forgiveness for your negligence in delivering the trust and for neglecting it for years. Your repentance is to safeguard it and to search for its owner or his brother to hand it over to him, and you must strive in your search and endure hardship. If you despair of reaching him, preserve his money until you find him, and you may give it in charity on his behalf, and inform him of what you did if you find him later. Then, either he approves the charity and its reward is for him, or he takes his money and the reward of the charity is for you.