Tailgating Rules

I’ve got 2 Season Tickets with a Yellow Lot parking pass. I’ve sold my tickets to the Cleveland game for basically peanuts, but a group of us want to tailgate for the game. It’s been a while since I’ve tailgated, so I was wondering if can you still tailgate with just a parking pass? If so, can I bring along 3-5 people in my truck just to tailgate, or do we all need tickets to the actual game.