What is the expiation for not performing the ritual of Rami al-Jamarat during Hajj due to fatigue from varicose veins?

Stoning the Jamarat is one of the obligatory rites of Hajj. Whoever neglects it until the time for stoning has passed, without a valid excuse, is sinful and must offer a sacrifice (dam). If one neglects it due to a valid excuse, then a sacrifice (dam) is still required, but there is no sin. The sacrifice (dam) involves slaughtering a sheep in the Haram and distributing its meat to the poor of the Haram.