Pat fish dry and season each fillet with 1 Tbsp rub and ½ Tbsp olive oil. Let marinade for 10 minutes up to 1 hour.
Season zucchini and squash with remaining 2 Tbsp olive oil and sea salt.
Meanwhile to make the glaze in a small pot over medium heat melt the butter. Add the remaining glaze ingredients and stir until well combined.
Heat grill to 500F. Add zucchini and squash to grill and cook until tender and grill marks appear, about 5-6 minutes per side.
Add fish to grill and brush with glaze. Cook for 3 minutes then flip and brush the other side with glaze. Cook another 3-4 minutes or until you’ve reached your desired doneness.
