How did Tarkhad's experience with the grapes help confirm the miracle for Dharamsee?

Tarkhad's presence and experience were crucial in confirming the personal nature of the miracle for Dharamsee. After Dharamsee was amazed to find his grapes were seedless, he sought external validation. Chapter 35 narrates that he turned to Tarkhad, who was also receiving grapes from the same distribution, and asked him what his were like. Tarkhad replied that his grapes did, in fact, have seeds. This confirmation made Dharamsee 'extremely surprised' because it proved that the transformation of the grapes was not a general occurrence but a specific, personal miracle performed by Baba in direct response to his own thoughts and doubts.