Suppose Ahmad has not pray isha because of traveling on a plane. And Ahmad said that to Ibrahim. And before paying the isha pray, Ahmad died. Can Ibrahim pray at the place of Ahmad. And generally can a person pray at the place of another person.
No another person can't allowed to perform someone prayer because everyone have to answer and responsible for his or her own actions. And prayer is obligated on every Muslim on a certain period of time so everyone have to perform his own prayer. Allah granted us with qaza namaz if you are not able to perform prayer you can perform it later which is called qaza.