The ruling on one who is unable to fulfill his vow

Shaykh Abdul Aziz, the first message received for this episode of the program came from the brother Isa Hasan Ghazi from Jeddah, or Azab: Our brother says: Please send your message to your eminence, and I hope you will graciously present the questions and inquiries contained therein to one of the eminent scholars, may Allah honor them.
I am a young man of twenty-six years. Allah decreed upon me one of the trials of this world that befall every young man and every married Muslim. I have three sons who live under my care, after Allah, and my mother is advanced in age. The divine decrees have prevented me from seeing them for approximately one year and six months. I vowed to Allah that upon my return to my home and my children, who have been under the care of the charitable during my absence, I would fast six days for Allah the Exalted in gratitude and thanks to Allah, slaughter two sacrificial animals for Allah the Exalted, and visit Makkah and Madinah with my father. I would also carry my mother on my shoulders to perform the tawaf and sa'y with her. When that trial passed, and due to my poor financial condition and that of my family, I slaughtered only one sacrificial animal and was unable to bring the other. Likewise, I was unable to take my family and my mother to Makkah and Madinah to fulfill my vow due to my poor financial condition, and I was even unable to perform the fast. Fearing that I would fall into sin and burden, I sent this message hoping, perhaps, to find the simplest way to draw near to Allah and fulfill what I vowed. I am a young man who is careful to perform the obligatory and voluntary prayers, even at night and during the Duha prayer. I beseech the Most High, the Almighty, to grant you success in answering, may Allah protect you?
Answer: In the name of Allah, the Most Gracious, the Most Merciful. Praise be to Allah, and may Allah send prayers and blessings upon the Messenger of Allah, and upon his family and his Companions, and upon those who follow his guidance.
As for what follows:
So praise be to Allah who has made it easy for you to reunite with your parents and children, and we ask Him, Exalted and Majestic is He, to improve the condition of you all, and to help you in what He loves and is pleased with.
As for the vow, it is obligatory for you to fulfill it according to your ability. Allah has praised the believers who fulfill their vows in His saying, Exalted and Majestic is He: [Al-Insan:7]. And the Prophet (peace and blessings be upon him) said: , narrated by the Imam al-Bukhari in his Sahih from Aisha (may Allah be pleased with her).
So you must perform the second sacrifice when you are able [Al-Baqarah:286]. When you are able and it becomes easy for you to buy the second sacrificial animal, do so, slaughter it, and give it in charity to the poor, unless you intended to eat it with your family; in that case, you are on your intention. This is based on the saying of the Prophet (peace and blessings be upon him): .
As for if you vowed to slaughter but did not intend to eat it with your family, then you give it to the poor.
And you must fast six days when it becomes easy for you; because it is an act of obedience to Allah. So you must fast them when you are able, even if they are scattered, unless you intended to fast them consecutively; in that case, you are on your intention. For deeds are by intentions. If you intended them to be consecutive, fast them consecutively to fulfill your vow and your intention. As for if you did not intend consecutiveness, then you fast them even if scattered, and there is no blame in that.
And you must also perform Hajj with your parents. You take your parents to Makkah and to Madinah as you vowed. If you intended 'Umrah, then 'Umrah, and if you intended Hajj, then Hajj, according to your intention in going to Makkah. If you intended 'Umrah with them, 'Umrah is sufficient. If you intended Hajj, then you must perform Hajj with them when you are able [Al-Baqarah:286]. And He says, Exalted is He: [At-Taghabun:16]. And you must also take them to Madinah; because traveling to Madinah for prayer in the Prophet's Mosque (peace and blessings be upon him) is a recommended practice and a nearness to Allah. And when you visit Madinah, you greet the Messenger (peace and blessings be upon him) and his two companions. This is the best for you. Visiting his grave (peace and blessings be upon him) and the graves of his two companions is prescribed for one who is in Madinah. It is prescribed. What is forbidden is traveling solely for the purpose of visiting graves. As for traveling for the mosque, and the visit is included in that, there is no harm. So greet the Prophet (peace and blessings be upon him) and his two companions (may Allah be pleased with them both). As for women, they do not visit graves, but you and your father and the men with you.
As for women, they do not visit graves, but they pray in the Prophet's Mosque (peace and blessings be upon him) and send blessings upon him in their place in the mosque, in the houses, and on the road. May Allah send blessings and peace upon him and his family and his companions.
And it is prescribed for you—O men—you and the men with you—to visit al-Baqi' and visit the martyrs. All of this is prescribed for men: visiting graves. It is also recommended for you and those with you, both women and men, to visit the Mosque of Quba and pray in it; because it is an excellent mosque, and visiting it is recommended for one who is in Madinah.
As for your carrying your mother or your parents to perform Hajj with them and carrying them, no, that is not upon you. But your mother performs tawaf by herself, and your father performs tawaf by himself, and each of them performs sa'y by himself, or in a cart if it is difficult for them. Praise be to Allah, the matter is broad. As for carrying them, it is not upon you to carry them. Rather, you expiate this vow of carrying them with the expiation of an oath for carrying them. You must perform the expiation of an oath for carrying them, which is feeding ten poor people or clothing them. Ten people, you give each one half a sa' of dates, or wheat, or rice. Or you clothe each one with a garment that suffices them in prayer, such as a shirt, or an izar and a rida, and that is sufficient. It is not upon you to carry them. Rather, they perform tawaf by themselves and sa'y by themselves. And if they are unable, they are carried for tawaf and sa'y, and praise be to Allah.
And we ask Allah to help you in fulfilling it and to accept from us and from you. We advise you not to make vows. We advise you in the future not to make vows, because the Messenger (peace be upon him) said: . So we advise you in the future not to make vows ever. Even if good things happen to you, thank Allah, obey Allah, and praise Him, but there is no need for a vow.
And you said in your words, "But the decrees prevented me." The best is to say in such a case: "But Allah decreed such and such." Because the decrees do not act except by the action of Allah alone. So you say in such a case, "Allah decreed upon me such and such," "Allah decreed such and such," "I am unable to do such and such," "I am delayed from my children such and such." You express it by attributing the matter to Allah, Glorified and Exalted is He. "Allah decreed upon me such and such" or "Allah willed such and such." This is what is prescribed.
May Allah grant us and you beneficial knowledge and righteous deeds. Yes.