BRING first 4 ingredients to boil in small saucepan. Simmer on low heat 10 min., stirring occasionally. Cool.
COMBINE squash, zucchini, onions and fennel in large bowl. Add 1 Tbsp. oil; toss to evenly coat vegetables with oil. Grill 5 to 7 min. or until vegetables are crisp-tender, turning occasionally. Remove from grill.
RESERVE 1 Tbsp. of the remaining oil for later use. Brush steaks with remaining oil; season with 1 Tbsp. pepper and salt. Grill 8 to 10 min. on each side or until steaks are medium doneness (160°F). Transfer to cutting board.
TOSS scallops with 1 tsp. of the reserved oil; season with remaining pepper. Grill 2 min. on each side or until opaque. Remove from grill.
CUT fennel bulb into thin slices; place in medium bowl. Chop enough of the fennel fronds to measure 2 Tbsp. Add to sliced fennel along with the squash, zucchini, lemon zest, juice and remaining oil.
PLACE 2 onions in food processor with date mixture; process until smooth.
CUT steaks and scallops in half; place on platter with tomato slices and remaining onions. Serve with date sauce and vegetable salad.