What is required of one who says: If such and such happens to me, then I must do such and such?

This is also a letter from Salim Muhammad al-Zahrani, who sent it saying: A while ago, more than a year ago, in a certain area, I had some colleagues, and I said to them: If such and such happens to me, then I owe you a sacrificial animal with these exact words. And naturally, what I intended did happen. But I traveled and moved away from these colleagues suddenly due to work, and I did not remember it until after I had left that area where I had made this vow specifically for those people. The question is: Am I required to fulfill my vow in my current location, or in any place with any people, knowing that it is not possible for me to return to my previous residence? Please accept my greetings.
Answer: This is not a vow. If he says: If such and such happens to me, then I owe you such and such, this is not a vow; this is a promise. A vow is when one says: Charity for the sake of Allah, or a vow upon me for Allah if Allah heals me, or if such and such happens to me, that I will do such and such, that I will fast such and such, that I will give charity of such and such. This is a vow. As for saying: If such and such happens to me, I will give them such and such, or I will slaughter a sacrificial animal for you, this is a promise and not a vow. If he slaughters for them, there is no harm; and if he does not, there is no harm; it is not required of him. If it becomes easy for him and he slaughters for them, that is good. But if he makes a vow and says: Charity for the sake of Allah is upon me, or a vow upon me for Allah that I will do such and such if such and such happens, then he must fulfill his vow. A vow of obedience, if it is for the poor and the needy, or a prayer or a lawful fast, there is no harm. But if he vows for a specific person, saying: A vow upon me for Allah, or charity for the sake of Allah is upon me, if Allah heals me, that I will give so-and-so such and such, or clothe him, and he is poor and deserves it, then he must fulfill it. Yes.