In any case, you are a trustee. You are only required to carry out the instructions you were given, and you must not dispose of this zakat without authorization from its owner.
Question: He has designated specific names, yet someone more deserving might come and receive nothing because the money was earmarked for someone else. Is this not problematic?
Answer: That is his responsibility. If the named individuals are legitimate recipients, there is no harm in restricting the zakat to them. If, however, they are not entitled to zakat, it is impermissible for him to give it to those who have no right to it. Should the named persons be eligible while others exist who are in even greater need, it is preferable to give the zakat to those who are more destitute; nonetheless, giving it to the original recipients still fulfils the obligation.
Disbursing zakat to poor relatives
Question: I have several full brothers and sisters. Each has a large family and virtually nothing with which to cover their children’s schooling expenses, whereas I am in better circumstances, praise be to Allah. May I distribute my zakat to them without telling them it is zakat, so as to spare them embarrassment and because they might refuse if they knew?
Answer: It is permissible to give zakat to such relatives, for they are in need as long as their income does not cover their essential requirements. Paying zakat to them is legislated, but do not hand it to each individual. Rather, give it to their guardian—the one who maintains and supports them.