Take a deep breath Mo
Take the control back
He has asked to see the dc, and you've made an offer. He's now changed that to someone cooking lunch and having a house full of his friends and family.
So, he either wants to spend time with his dc OR he wants a big lunch party. I don't think the two things are compatible
He can get these friends to pick him up after lunch, considering the situation that's the only way you will feel comfortable. He's going to have to decide what's important to him. His arrangements aren't your concern any more - you're not a couple.
If it was me I wouldn't go back to a house full of his friends and family, it's your home, and you'd feel even more intimidated