Expiation for vow of hajj

Salaam, I trust you are in good health. I would like to inquire about a situation concerning an individual who pledged to perform Hajj while battling cancer. In their exact words, they said, "Oh Allah, if I regain my health, I will undertake the Hajj pilgrimage." It has been almost 20 years since this vow has been made and it stands unfulfilled.I came across a passage in Al-Hidaya which suggests that according to Imam Abu Hanifa and Imam Muhammad, expiation may serve as a substitute for fulfilling this vow. Excerpt from Hidaya: "If he links the vow of consecration to a condition, and the condition is found, then he must fulfil the vow itself, due to the absolute terms of the tradition, because what is suspended on a condition is one that requires immediate performance in his view. It is narrated from Abu Hanifah (God bless him) that he withdrew that opinion and said: If he says, "If I do such and such thing then I am under an obligation to perform hajj or to fast for a year or give in charity what I own," it is to be deemed compensated through expiation for the vow. This is also the view of Muhammad (God bless him)" We would highly appreciate it if you could provide clarity on the matter.