What are the implications for the heirs and the investor of terminating the verbal sharecropping contract, after the owner's death and the investor's cessation of cultivating the land?

It is permissible to engage in sharecropping (Muzara'ah), whether the seeds and expenses are provided by the landowner or the worker. This is the correct view, and 'Umar permitted it.

Giving money to your father, the worker, is classified as a loan. This constitutes a combination of a loan and sharecropping. The majority of jurists have permitted this because sharecropping is not a contract of exchange (mu'awadah); rather, it is a contract intended for profit, like a partnership (sharika) or profit-sharing (mudarabah).

Sharecropping is terminated upon the death of one of the contracting parties (the landowner or the worker), according to the Hanafis and Hanbalis. Therefore, the heirs of the deceased must annul the contract and return the loan, and any existing harvest is divided according to the agreed-upon proportion.