Preheat a grill to high. Thread the strawberries onto skewers and place on the grill. Cook, turning frequently, until lightly charred, 5 to 7 minutes; transfer to a bowl. Lower the heat to medium. Brush the pound cake slices on both sides with the melted butter. Grill, turning once, until toasted and grill marks appear, about 8 minutes.
Coarsely chop the strawberries. In a medium bowl, using a handheld mixer, beat the cream cheese with the sugar until smooth. Beat in the heavy cream until soft peaks form, about 3 minutes. Stir in three-quarters of the chopped strawberries.
Brush the cake slices with the jelly, then spread each with 3 tablespoons of the strawberry cream. Stack them in twos, cream side up, to make 6 double-decker stacks. Dollop each with the remaining strawberry cream and chopped strawberries.