Is it permissible to convert the pledged sum from Kuwaiti Dinars to Egyptian Pounds? Is it permissible to give it to a party other than our brethren in Palestine? Am I required to offer expiation for that?

If a Muslim vows an act of obedience, he is obligated to fulfill it as he vowed it. Fulfilling vows is a characteristic of the righteous and pious. Therefore, the vowed money must be given only to the Palestinian brethren, and it is not permissible to give it to an institute or another party. It is permissible to pay the amount in any other currency that is more suitable for them and easier to utilize, provided that its value does not decrease from its originally specified amount. If the full amount reaches them, there is no fault or expiation, because what is required is the complete fulfillment of the vow.