Light a grill. Place the peach and plum halves on the hottest portion of the grill and cook, flipping once, until lightly charred but still firm, 6 to 8 minutes. Add the cherries to the grill for the last 2 minutes, turning them as needed until lightly charred. Transfer all the grilled fruit to a plate to let cool. Then roughly chop.
In a small saucepan over high heat, combine the sugar and water. Cook until the sugar has dissolved, 2 minutes. Then, remove from the heat and add the lemon zest, rose water and salt. Let cool completely.
In a large 2-liter pitcher, combine the chopped fruit and syrup with the rosé and peach brandy. Cover and refrigerate overnight to steep. The next day, add ice and serve.