Is it permissible to pay the expiation for an oath (kaffarat al-yamin) to free a slave who is sought for 20 million [dirhams/dinars]?

The expiation for an oath is feeding ten poor persons, or clothing them, or freeing a slave. If one cannot find any of these, then he must fast for three days. Scholars have differed on the permissibility of paying the monetary value for the expiation. The majority opinion is that paying the value is not sufficient, while some scholars hold that it is sufficient, especially if it is more beneficial for the poor.