Is it permissible for a person who has not performed the obligatory Hajj to send someone to perform Hajj on behalf of his deceased parents, using money earned from his work washing dishes in a restaurant that serves pork and alcohol, knowing that his parents left him nothing but agricultural land?

The correct view is that Hajj is obligatory immediately for whoever meets the conditions of capability (istita'ah), based on the Prophet's (peace and blessings be upon him) saying: "Hasten to Hajj" - meaning the obligatory Hajj - "for none of you knows what may befall him."

If the questioner meets the conditions of capability, he must hasten to perform Hajj, especially since he has reached this age.

If he delegates someone to perform Hajj on behalf of his parents, and that person has already performed Hajj for himself, then the Hajj for the parents is valid. However, he is mistaken by delaying his own Hajj.

If the land left by the questioner's father exceeds his needs, and he was able to sell it to perform Hajj with its price but did not do so, then Hajj became an obligation upon him (in his accountability), and someone must be delegated to perform Hajj on his behalf from that land.

The questioner's work is impermissible because it involves assisting in what is unlawful, and he must search for another job as soon as possible.

Hajj performed with unlawful money is not permissible; rather, the expense of Hajj must come from pure earnings.