Bequeathing the performance of Hajj on behalf of her father and her son performing Hajj from her own money

Q: While my mother was sick and my maternal uncle and myself were staying with her, she entrusted us with performing Hajj on behalf of her father. It may be worth mentioning that my maternal uncle is not my mother's brother. Rather, he is her cousin. However, my mother died so I called my uncle and mentioned my mother's will. My uncle replied that he did not hear it. Any way, I performed Hajj on behalf of my maternal grandfather and paid for it out of my mother's money and my own money which was originally earned by my father. Nevertheless, (Part No. 16; Page No. 345) I do not know whether I implemented my mother's will or not bearing in mind that my mother had performed her Hajj and I had performed my Hajj before performing it on behalf of my maternal grandfather. On the other hand, my uncle mentioned above came afterwards to me and asked to pay half of the costs of Hajj (that I performed on behalf of my maternal grandfather). I refused and told him that I was the only person who had to bear the costs of the implementation of the will of my mother. Please provide me with your beneficial opinion in this regard. Shall I let my uncle share the costs of the concerned Hajj or is it sufficient that I have paid for that Hajj from my mother's and my own money because my maternal grandfather is the paternal uncle of my uncle?

A: If the reality is exactly as you have mentioned, the Hajj that you performed for your maternal grandfather is sufficient for the implementation of her will. On the other hand, it is Wajib (obligatory) not to divide the costs of the concerned Hajj between you and your uncle. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.