I don't think it is dead, quite. Did you plant it from a pot, and if so was the pot well-watered before transplanting? Had you watered it any other time in the month between planting and the recent watering? Past a certain point, if a plant gets too dry the more shrivelled leaves won't return to normal but the plant may survive. Is that pesticide primarily neem oil?
Edited to add, is that poison ivy behind the Monarda on the left?
