You are a high value target. Your dad is hosting a big party. When the TaskForce receive news of this, they knew they had to go even though they unfortunately had to dress up. They knew you were going to be there so they had to go.

Ghost, Price, Gaz, Soap, and Alejandro all get suited up and ready to go to the party. When they arrive, they all act like the other rich, classy people and blend in. Then you come out.