Did everyone who received grapes from Baba that day have the same miraculous experience as Dharamsee?

No, the miracle of the seedless grapes was a personal experience specifically for Boss Dharamsee. Chapter 35 makes a point to contrast his experience with that of another devotee. After being amazed that his grapes were seedless, Dharamsee asked Tarkhad, who was also present and receiving grapes from Baba, about his own portion. The text clearly states that when Dharamsee asked him, "How were your grapes?", Tarkhad replied that his grapes did have seeds. This revelation caused Dharamsee to be "extremely surprised in his heart," confirming that the miracle was not a general occurrence but a specific, targeted act by Baba to address Dharamsee's personal skepticism and thoughts.