Is it permissible to donate 5,000 pounds to orphans, knowing that the deceased father had entered into a Mudarabah contract with this amount intending for it and the profit to be an endowment (waqf) for specific poor people?

If the father explicitly stated that the money is an endowment (waqf) and its proceeds are for specific poor individuals, then it is not permissible to donate it to orphans. Rather, it must remain an endowment because it cannot be sold, gifted, or inherited. The condition of the endower (waqif) must be fulfilled, which is the preservation of the principal sum and the benefit of the specified individuals from its proceeds. The money can be invested in a Mudarabah partnership or in any lawful way, provided that its proceeds are given to those designated by the endower. The endowment of cash is permissible for lending or trading with it, and then giving its profits in charity to the beneficiaries.