Is it permissible to complete a Kaffarah (expiation) by fasting if one has partially fulfilled it with feeding, clothing, or manumission but lacks the means to complete the required full act?

Primary text

It is not permissible to complete an expiation by fasting if one has only partially performed the expiation through feeding the poor, clothing them, or freeing half a slave, and subsequently lacks the means to complete the remainder. This is because fasting acts as a substitute (badal) for the primary requirements of the expiation, and one cannot complete a required act through a substitute when the primary act itself was only partially completed, similar to other substitutions. Furthermore, fasting is a substitute for feeding, and manumission/clothing is further removed from feeding; thus, if one form of substitute cannot complete the other type of primary fulfillment, completing the primary act with a secondary substitute is less valid. This situation is differentiated from the usage of Tayammum (dry ablution) for Wudu or Ghusl, because Tayammum is performed as a complete substitute for the entire purity rite, whereas here, fasting the entire expiation would be sufficient if done initially.